From ab05acbf89a4774eeb7f8958f8356ff122d737ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 7 May 2018 16:54:15 +0200
Subject: [PATCH 01/27] core: Mark openocd info variables read-only

---
 core/sched.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/core/sched.c b/core/sched.c
index 84151433d041..0bd9e0e31771 100644
--- a/core/sched.c
+++ b/core/sched.c
@@ -65,13 +65,13 @@ static uint32_t runqueue_bitcache = 0;
 #endif
 
 FORCE_USED_SECTION
-uint8_t max_threads = sizeof(sched_threads) / sizeof(thread_t*);
+const uint8_t max_threads = sizeof(sched_threads) / sizeof(thread_t*);
 
 #ifdef DEVELHELP
 /* OpenOCD can't determine struct offsets and additionally this member is only
  * available if compiled with DEVELHELP */
 FORCE_USED_SECTION
-uint8_t _tcb_name_offset = offsetof(thread_t, name);
+const uint8_t _tcb_name_offset = offsetof(thread_t, name);
 #endif
 
 #ifdef MODULE_SCHEDSTATISTICS

From e52500a75bc42c797e8dac4929f892d4e446a137 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Sat, 11 Aug 2018 07:44:04 +0200
Subject: [PATCH 02/27] cortexm_common: Binutils 2.30 ldscript unmodified

---
 cpu/cortexm_common/ldscripts/cortexm_base.ld | 364 ++++++++++++-------
 1 file changed, 232 insertions(+), 132 deletions(-)

diff --git a/cpu/cortexm_common/ldscripts/cortexm_base.ld b/cpu/cortexm_common/ldscripts/cortexm_base.ld
index c6413900cae1..b43ec5b379c1 100644
--- a/cpu/cortexm_common/ldscripts/cortexm_base.ld
+++ b/cpu/cortexm_common/ldscripts/cortexm_base.ld
@@ -1,33 +1,12 @@
-/* ----------------------------------------------------------------------------
- *         SAM Software Package License
- * ----------------------------------------------------------------------------
- * Copyright (c) 2012, Atmel Corporation
- *
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following condition is met:
- *
- * - Redistributions of source code must retain the above copyright notice,
- * this list of conditions and the disclaimer below.
- *
- * Atmel's name may not be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
- * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
- * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- * ----------------------------------------------------------------------------
- */
-
-OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
+/* Copyright (C) 2014-2018 Free Software Foundation, Inc.
+   Copying and distribution of this script, with or without modification,
+   are permitted in any medium without royalty provided the copyright
+   notice and this notice are preserved.  */
+
+/* Based on the default ldscript in GNU binutils 2.30, adjusted for ROM->RAM
+ * relocations */
+/* Script for -z combreloc -z now -z relro: combine and sort reloc sections */
+OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
 OUTPUT_ARCH(arm)
 SEARCH_DIR(.)
 
@@ -37,115 +16,236 @@ ENTRY(reset_handler_default)
 /* Section Definitions */
 SECTIONS
 {
-    .text :
+    /* Read-only sections, merged into text segment: */
+    PROVIDE (__executable_start = SEGMENT_START("text-segment", 0x8000)); . = SEGMENT_START("text-segment", 0x8000);
+    .interp         : { *(.interp) }
+    .note.gnu.build-id : { *(.note.gnu.build-id) }
+    .hash           : { *(.hash) }
+    .gnu.hash       : { *(.gnu.hash) }
+    .dynsym         : { *(.dynsym) }
+    .dynstr         : { *(.dynstr) }
+    .gnu.version    : { *(.gnu.version) }
+    .gnu.version_d  : { *(.gnu.version_d) }
+    .gnu.version_r  : { *(.gnu.version_r) }
+    .rel.dyn        :
     {
-        . = ALIGN(4);
-        _sfixed = .;
-        _isr_vectors = DEFINED(_isr_vectors) ? _isr_vectors : . ;
-        KEEP(*(SORT(.vectors*)))
-        *(.text .text.* .gnu.linkonce.t.*)
-        *(.glue_7t) *(.glue_7)
-        *(.rodata .rodata* .gnu.linkonce.r.*)
-        *(.ARM.extab* .gnu.linkonce.armextab.*)
-
-        /* Support C constructors, and C destructors in both user code
-           and the C library. This also provides support for C++ code. */
-        . = ALIGN(4);
-        KEEP(*(.init))
-        . = ALIGN(4);
-        __preinit_array_start = .;
+        *(.rel.init)
+        *(.rel.text .rel.text.* .rel.gnu.linkonce.t.*)
+        *(.rel.fini)
+        *(.rel.rodata .rel.rodata.* .rel.gnu.linkonce.r.*)
+        *(.rel.data.rel.ro .rel.data.rel.ro.* .rel.gnu.linkonce.d.rel.ro.*)
+        *(.rel.data .rel.data.* .rel.gnu.linkonce.d.*)
+        *(.rel.tdata .rel.tdata.* .rel.gnu.linkonce.td.*)
+        *(.rel.tbss .rel.tbss.* .rel.gnu.linkonce.tb.*)
+        *(.rel.ctors)
+        *(.rel.dtors)
+        *(.rel.got)
+        *(.rel.bss .rel.bss.* .rel.gnu.linkonce.b.*)
+        PROVIDE_HIDDEN (__rel_iplt_start = .);
+        *(.rel.iplt)
+        PROVIDE_HIDDEN (__rel_iplt_end = .);
+    }
+    .rela.dyn       :
+    {
+        *(.rela.init)
+        *(.rela.text .rela.text.* .rela.gnu.linkonce.t.*)
+        *(.rela.fini)
+        *(.rela.rodata .rela.rodata.* .rela.gnu.linkonce.r.*)
+        *(.rela.data .rela.data.* .rela.gnu.linkonce.d.*)
+        *(.rela.tdata .rela.tdata.* .rela.gnu.linkonce.td.*)
+        *(.rela.tbss .rela.tbss.* .rela.gnu.linkonce.tb.*)
+        *(.rela.ctors)
+        *(.rela.dtors)
+        *(.rela.got)
+        *(.rela.bss .rela.bss.* .rela.gnu.linkonce.b.*)
+        PROVIDE_HIDDEN (__rela_iplt_start = .);
+        *(.rela.iplt)
+        PROVIDE_HIDDEN (__rela_iplt_end = .);
+    }
+    .rel.plt        :
+    {
+        *(.rel.plt)
+    }
+    .rela.plt       :
+    {
+        *(.rela.plt)
+    }
+    .init           :
+    {
+        KEEP (*(SORT_NONE(.init)))
+    }
+    .plt            : { *(.plt) }
+    .iplt           : { *(.iplt) }
+    .text           :
+    {
+        *(.text.unlikely .text.*_unlikely .text.unlikely.*)
+        *(.text.exit .text.exit.*)
+        *(.text.startup .text.startup.*)
+        *(.text.hot .text.hot.*)
+        *(.text .stub .text.* .gnu.linkonce.t.*)
+        /* .gnu.warning sections are handled specially by elf32.em.  */
+        *(.gnu.warning)
+        *(.glue_7t) *(.glue_7) *(.vfp11_veneer) *(.v4_bx)
+    }
+    .fini           :
+    {
+        KEEP (*(SORT_NONE(.fini)))
+    }
+    PROVIDE (__etext = .);
+    PROVIDE (_etext = .);
+    PROVIDE (etext = .);
+    .rodata         : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+    .rodata1        : { *(.rodata1) }
+    .ARM.extab   : { *(.ARM.extab* .gnu.linkonce.armextab.*) }
+    PROVIDE_HIDDEN (__exidx_start = .);
+    .ARM.exidx   : { *(.ARM.exidx* .gnu.linkonce.armexidx.*) }
+    PROVIDE_HIDDEN (__exidx_end = .);
+    .eh_frame_hdr : { *(.eh_frame_hdr) *(.eh_frame_entry .eh_frame_entry.*) }
+    .eh_frame       : ONLY_IF_RO { KEEP (*(.eh_frame)) *(.eh_frame.*) }
+    .gcc_except_table   : ONLY_IF_RO { *(.gcc_except_table
+    .gcc_except_table.*) }
+    .gnu_extab   : ONLY_IF_RO { *(.gnu_extab*) }
+    /* These sections are generated by the Sun/Oracle C++ compiler.  */
+    .exception_ranges   : ONLY_IF_RO { *(.exception_ranges
+    .exception_ranges*) }
+    /* Adjust the address for the data segment.  We want to adjust up to
+       the same address within the page on the next page up.  */
+    . = ALIGN(CONSTANT (MAXPAGESIZE)) + (. & (CONSTANT (MAXPAGESIZE) - 1));
+    /* Exception handling  */
+    .eh_frame       : ONLY_IF_RW { KEEP (*(.eh_frame)) *(.eh_frame.*) }
+    .gnu_extab      : ONLY_IF_RW { *(.gnu_extab) }
+    .gcc_except_table   : ONLY_IF_RW { *(.gcc_except_table .gcc_except_table.*) }
+    .exception_ranges   : ONLY_IF_RW { *(.exception_ranges .exception_ranges*) }
+    /* Thread Local Storage sections  */
+    .tdata	  : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
+    .tbss		  : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) }
+    .preinit_array     :
+    {
+        PROVIDE_HIDDEN (__preinit_array_start = .);
         KEEP (*(.preinit_array))
-        __preinit_array_end = .;
-
-        . = ALIGN(4);
-        __init_array_start = .;
-        KEEP (*(SORT(.init_array.*)))
-        KEEP (*(.init_array))
-        __init_array_end = .;
-
-        . = ALIGN(0x4);
+        PROVIDE_HIDDEN (__preinit_array_end = .);
+    }
+    .init_array     :
+    {
+        PROVIDE_HIDDEN (__init_array_start = .);
+        KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
+        KEEP (*(.init_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .ctors))
+        PROVIDE_HIDDEN (__init_array_end = .);
+    }
+    .fini_array     :
+    {
+        PROVIDE_HIDDEN (__fini_array_start = .);
+        KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))
+        KEEP (*(.fini_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .dtors))
+        PROVIDE_HIDDEN (__fini_array_end = .);
+    }
+    .ctors          :
+    {
+        /* gcc uses crtbegin.o to find the start of
+           the constructors, so we make sure it is
+           first.  Because this is a wildcard, it
+           doesn't matter if the user does not
+           actually link against crtbegin.o; the
+           linker won't look for a file to match a
+           wildcard.  The wildcard also means that it
+           doesn't matter which directory crtbegin.o
+           is in.  */
         KEEP (*crtbegin.o(.ctors))
-        KEEP (*(EXCLUDE_FILE (*crtend.o) .ctors))
+        KEEP (*crtbegin?.o(.ctors))
+        /* We don't want to include the .ctor section from
+           the crtend.o file until after the sorted ctors.
+           The .ctor section from the crtend file contains the
+           end of ctors marker and it must be last */
+        KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .ctors))
         KEEP (*(SORT(.ctors.*)))
-        KEEP (*crtend.o(.ctors))
-
-        . = ALIGN(4);
-        KEEP(*(.fini))
-
-        . = ALIGN(4);
-        __fini_array_start = .;
-        KEEP (*(.fini_array))
-        KEEP (*(SORT(.fini_array.*)))
-        __fini_array_end = .;
-
+        KEEP (*(.ctors))
+    }
+    .dtors          :
+    {
         KEEP (*crtbegin.o(.dtors))
-        KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
+        KEEP (*crtbegin?.o(.dtors))
+        KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .dtors))
         KEEP (*(SORT(.dtors.*)))
-        KEEP (*crtend.o(.dtors))
-
-        . = ALIGN(4);
-        _efixed = .;            /* End of text section */
-    } > rom
-
-    /* .ARM.exidx is sorted, so has to go in its own output section.  */
-    PROVIDE_HIDDEN (__exidx_start = .);
-    .ARM.exidx :
+        KEEP (*(.dtors))
+    }
+    .jcr            : { KEEP (*(.jcr)) }
+    .data.rel.ro : { *(.data.rel.ro.local* .gnu.linkonce.d.rel.ro.local.*) *(.data.rel.ro .data.rel.ro.* .gnu.linkonce.d.rel.ro.*) }
+    .dynamic        : { *(.dynamic) }
+    .got            : { *(.got.plt) *(.igot.plt) *(.got) *(.igot) }
+    .data           :
     {
-      *(.ARM.exidx* .gnu.linkonce.armexidx.*)
-    } > rom
-    PROVIDE_HIDDEN (__exidx_end = .);
-
-    /* exception handling */
-    . = ALIGN(4);
-    .eh_frame :
+        __data_start = . ;
+        *(.data .data.* .gnu.linkonce.d.*)
+        SORT(CONSTRUCTORS)
+    }
+    .data1          : { *(.data1) }
+    _edata = .; PROVIDE (edata = .);
+    . = .;
+    __bss_start = .;
+    __bss_start__ = .;
+    .bss            :
     {
-        KEEP (*(.eh_frame))
-    } > rom
-
-    . = ALIGN(4);
-    _etext = .;
-
-    /* stack section */
-    .stack (NOLOAD):
-    {
-        KEEP (*(.puf))
-        . = ALIGN(8);
-        _sstack = .;
-        KEEP (*(.isr_stack))
-        . = ALIGN(8);
-        _estack = .;
-    } > ram
-
-    .relocate :
-    {
-        . = ALIGN(4);
-        _srelocate = .;
-        *(.ramfunc .ramfunc.*);
-        *(.data .data.*);
-        KEEP (*(.openocd .openocd.*))
-        . = ALIGN(4);
-        _erelocate = .;
-    } > ram AT> rom
-
-    /* .bss section which is used for uninitialized data */
-    .bss (NOLOAD) :
-    {
-        . = ALIGN(4);
-        _sbss = . ;
-        _szero = .;
-        *(.bss .bss.*)
+        *(.dynbss)
+        *(.bss .bss.* .gnu.linkonce.b.*)
         *(COMMON)
-        . = ALIGN(4);
-        _ebss = . ;
-        _ezero = .;
-    } > ram
-
-    /* heap section */
-    . = ALIGN(4);
-    _sheap = . ;
-    _eheap = ORIGIN(ram) + LENGTH(ram);
-
-    /* Populate information about ram size */
-    _sram = ORIGIN(ram);
-    _eram = ORIGIN(ram) + LENGTH(ram);
+        /* Align here to ensure that the .bss section occupies space up to
+           _end.  Align after .bss to ensure correct alignment even if the
+           .bss section disappears because there are no input sections.
+           FIXME: Why do we need it? When there is no .bss section, we don't
+           pad the .data section.  */
+        . = ALIGN(. != 0 ? 32 / 8 : 1);
+    }
+    _bss_end__ = . ; __bss_end__ = . ;
+    . = ALIGN(32 / 8);
+    . = SEGMENT_START("ldata-segment", .);
+    . = ALIGN(32 / 8);
+    __end__ = . ;
+    _end = .; PROVIDE (end = .);
+    .stack         0x80000 :
+    {
+        _stack = .;
+        *(.stack)
+    }
+    /* Stabs debugging sections.  */
+    .stab          0 : { *(.stab) }
+    .stabstr       0 : { *(.stabstr) }
+    .stab.excl     0 : { *(.stab.excl) }
+    .stab.exclstr  0 : { *(.stab.exclstr) }
+    .stab.index    0 : { *(.stab.index) }
+    .stab.indexstr 0 : { *(.stab.indexstr) }
+    .comment       0 : { *(.comment) }
+    /* DWARF debug sections.
+       Symbols in the DWARF debugging sections are relative to the beginning
+       of the section so we begin them at 0.  */
+    /* DWARF 1 */
+    .debug          0 : { *(.debug) }
+    .line           0 : { *(.line) }
+    /* GNU DWARF 1 extensions */
+    .debug_srcinfo  0 : { *(.debug_srcinfo) }
+    .debug_sfnames  0 : { *(.debug_sfnames) }
+    /* DWARF 1.1 and DWARF 2 */
+    .debug_aranges  0 : { *(.debug_aranges) }
+    .debug_pubnames 0 : { *(.debug_pubnames) }
+    /* DWARF 2 */
+    .debug_info     0 : { *(.debug_info .gnu.linkonce.wi.*) }
+    .debug_abbrev   0 : { *(.debug_abbrev) }
+    .debug_line     0 : { *(.debug_line .debug_line.* .debug_line_end ) }
+    .debug_frame    0 : { *(.debug_frame) }
+    .debug_str      0 : { *(.debug_str) }
+    .debug_loc      0 : { *(.debug_loc) }
+    .debug_macinfo  0 : { *(.debug_macinfo) }
+    /* SGI/MIPS DWARF 2 extensions */
+    .debug_weaknames 0 : { *(.debug_weaknames) }
+    .debug_funcnames 0 : { *(.debug_funcnames) }
+    .debug_typenames 0 : { *(.debug_typenames) }
+    .debug_varnames  0 : { *(.debug_varnames) }
+    /* DWARF 3 */
+    .debug_pubtypes 0 : { *(.debug_pubtypes) }
+    .debug_ranges   0 : { *(.debug_ranges) }
+    /* DWARF Extension.  */
+    .debug_macro    0 : { *(.debug_macro) }
+    .debug_addr     0 : { *(.debug_addr) }
+    .ARM.attributes 0 : { KEEP (*(.ARM.attributes)) KEEP (*(.gnu.attributes)) }
+    .note.gnu.arm.ident 0 : { KEEP (*(.note.gnu.arm.ident)) }
+    /DISCARD/ : { *(.note.GNU-stack) *(.gnu_debuglink) *(.gnu.lto_*) }
 }

From 5d67e563138e00ac0467b335c029c3579286e462 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 7 May 2018 16:55:35 +0200
Subject: [PATCH 03/27] cortexm_common: Update ldscript to be more similar to
 binutils default

---
 cpu/cortexm_common/ldscripts/cortexm_base.ld | 129 ++++++++++++-------
 cpu/cortexm_common/vectors_cortexm.c         |  15 +--
 2 files changed, 86 insertions(+), 58 deletions(-)

diff --git a/cpu/cortexm_common/ldscripts/cortexm_base.ld b/cpu/cortexm_common/ldscripts/cortexm_base.ld
index b43ec5b379c1..573b432497ce 100644
--- a/cpu/cortexm_common/ldscripts/cortexm_base.ld
+++ b/cpu/cortexm_common/ldscripts/cortexm_base.ld
@@ -16,8 +16,13 @@ ENTRY(reset_handler_default)
 /* Section Definitions */
 SECTIONS
 {
-    /* Read-only sections, merged into text segment: */
-    PROVIDE (__executable_start = SEGMENT_START("text-segment", 0x8000)); . = SEGMENT_START("text-segment", 0x8000);
+    /* Read-only sections, merged into rom segment: */
+    PROVIDE (__executable_start = SEGMENT_START("rom", 0x0)); . = SEGMENT_START("rom", 0x0);
+    .vectors        :
+    {
+        _isr_vectors = DEFINED(_isr_vectors) ? _isr_vectors : . ;
+        KEEP(*(SORT(.vectors*)))
+    }
     .interp         : { *(.interp) }
     .note.gnu.build-id : { *(.note.gnu.build-id) }
     .hash           : { *(.hash) }
@@ -96,49 +101,45 @@ SECTIONS
     PROVIDE (etext = .);
     .rodata         : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
     .rodata1        : { *(.rodata1) }
-    .ARM.extab   : { *(.ARM.extab* .gnu.linkonce.armextab.*) }
-    PROVIDE_HIDDEN (__exidx_start = .);
-    .ARM.exidx   : { *(.ARM.exidx* .gnu.linkonce.armexidx.*) }
-    PROVIDE_HIDDEN (__exidx_end = .);
-    .eh_frame_hdr : { *(.eh_frame_hdr) *(.eh_frame_entry .eh_frame_entry.*) }
+    .openocd        :
+    {
+        KEEP (*(.openocd .openocd.*))
+    } > rom
+    .ARM.extab      : { *(.ARM.extab* .gnu.linkonce.armextab.*) }
+     PROVIDE_HIDDEN (__exidx_start = .);
+    .ARM.exidx      : { *(.ARM.exidx* .gnu.linkonce.armexidx.*) }
+     PROVIDE_HIDDEN (__exidx_end = .);
+    .eh_frame_hdr   : { *(.eh_frame_hdr) *(.eh_frame_entry .eh_frame_entry.*) }
     .eh_frame       : ONLY_IF_RO { KEEP (*(.eh_frame)) *(.eh_frame.*) }
-    .gcc_except_table   : ONLY_IF_RO { *(.gcc_except_table
-    .gcc_except_table.*) }
+    .gcc_except_table   : ONLY_IF_RO { *(.gcc_except_table .gcc_except_table.*) }
     .gnu_extab   : ONLY_IF_RO { *(.gnu_extab*) }
     /* These sections are generated by the Sun/Oracle C++ compiler.  */
-    .exception_ranges   : ONLY_IF_RO { *(.exception_ranges
-    .exception_ranges*) }
-    /* Adjust the address for the data segment.  We want to adjust up to
-       the same address within the page on the next page up.  */
-    . = ALIGN(CONSTANT (MAXPAGESIZE)) + (. & (CONSTANT (MAXPAGESIZE) - 1));
-    /* Exception handling  */
-    .eh_frame       : ONLY_IF_RW { KEEP (*(.eh_frame)) *(.eh_frame.*) }
-    .gnu_extab      : ONLY_IF_RW { *(.gnu_extab) }
-    .gcc_except_table   : ONLY_IF_RW { *(.gcc_except_table .gcc_except_table.*) }
-    .exception_ranges   : ONLY_IF_RW { *(.exception_ranges .exception_ranges*) }
-    /* Thread Local Storage sections  */
-    .tdata	  : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
-    .tbss		  : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) }
-    .preinit_array     :
+    .exception_ranges   : ONLY_IF_RO { *(.exception_ranges .exception_ranges*) }
+    /* This violates § 3.2.4.1 of C++ ABI for the ARM Architecture.
+     * the .preinit_array, .init_array, and .fini_array sections must be writable,
+     * but must be treated as if they were read-only, to allow for dynamic
+     * loaders to remap addresses. Ignoring this rule and placing them in ROM
+     * saves RAM space. */
+    .preinit_array  :
     {
         PROVIDE_HIDDEN (__preinit_array_start = .);
         KEEP (*(.preinit_array))
         PROVIDE_HIDDEN (__preinit_array_end = .);
-    }
+    } > rom
     .init_array     :
     {
         PROVIDE_HIDDEN (__init_array_start = .);
         KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
         KEEP (*(.init_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .ctors))
         PROVIDE_HIDDEN (__init_array_end = .);
-    }
+    } > rom
     .fini_array     :
     {
         PROVIDE_HIDDEN (__fini_array_start = .);
         KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))
         KEEP (*(.fini_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .dtors))
         PROVIDE_HIDDEN (__fini_array_end = .);
-    }
+    } > rom
     .ctors          :
     {
         /* gcc uses crtbegin.o to find the start of
@@ -159,7 +160,7 @@ SECTIONS
         KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .ctors))
         KEEP (*(SORT(.ctors.*)))
         KEEP (*(.ctors))
-    }
+    } > rom
     .dtors          :
     {
         KEEP (*crtbegin.o(.dtors))
@@ -167,45 +168,69 @@ SECTIONS
         KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .dtors))
         KEEP (*(SORT(.dtors.*)))
         KEEP (*(.dtors))
-    }
+    } > rom
     .jcr            : { KEEP (*(.jcr)) }
-    .data.rel.ro : { *(.data.rel.ro.local* .gnu.linkonce.d.rel.ro.local.*) *(.data.rel.ro .data.rel.ro.* .gnu.linkonce.d.rel.ro.*) }
+    .data.rel.ro    : { *(.data.rel.ro.local* .gnu.linkonce.d.rel.ro.local.*) *(.data.rel.ro .data.rel.ro.* .gnu.linkonce.d.rel.ro.*) }
     .dynamic        : { *(.dynamic) }
     .got            : { *(.got.plt) *(.igot.plt) *(.got) *(.igot) }
+
+    /* Writable sections, must be relocated from ROM to RAM during early boot */
     .data           :
     {
-        __data_start = . ;
+        __data_start = .;
         *(.data .data.* .gnu.linkonce.d.*)
         SORT(CONSTRUCTORS)
-    }
-    .data1          : { *(.data1) }
+    } > ram AT> rom
+    __data_load_start = LOADADDR(.data);
+    .ramfunc        :
+    {
+        __ramfunc_start = .;
+        *(.ramfunc .ramfunc.*)
+    } > ram AT> rom
+    __ramfunc_end = .;
+    /* Exception handling  */
+    .eh_frame       : ONLY_IF_RW { KEEP (*(.eh_frame)) *(.eh_frame.*) } > ram AT> rom
+    .gnu_extab      : ONLY_IF_RW { *(.gnu_extab) } > ram AT> rom
+    .gcc_except_table   : ONLY_IF_RW { *(.gcc_except_table .gcc_except_table.*) } > ram AT> rom
+    .exception_ranges   : ONLY_IF_RW { *(.exception_ranges .exception_ranges*) } > ram AT> rom
+    /* Thread Local Storage sections  */
+    .tdata          : { *(.tdata .tdata.* .gnu.linkonce.td.*) } > ram AT> rom
+    .tbss           : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) } > ram AT> rom
+    .data1          : { *(.data1) } > ram AT> rom
+    __data_end = .;
     _edata = .; PROVIDE (edata = .);
-    . = .;
-    __bss_start = .;
-    __bss_start__ = .;
-    .bss            :
+    .bss (NOLOAD)   :
     {
+      _szero = .;
+      __bss_start = .;
+      __bss_start__ = .;
         *(.dynbss)
         *(.bss .bss.* .gnu.linkonce.b.*)
         *(COMMON)
-        /* Align here to ensure that the .bss section occupies space up to
-           _end.  Align after .bss to ensure correct alignment even if the
-           .bss section disappears because there are no input sections.
-           FIXME: Why do we need it? When there is no .bss section, we don't
-           pad the .data section.  */
-        . = ALIGN(. != 0 ? 32 / 8 : 1);
-    }
-    _bss_end__ = . ; __bss_end__ = . ;
-    . = ALIGN(32 / 8);
-    . = SEGMENT_START("ldata-segment", .);
+    } > ram
     . = ALIGN(32 / 8);
+    _bss_end__ = . ; __bss_end__ = . ;
+    _ezero = .;
     __end__ = . ;
     _end = .; PROVIDE (end = .);
-    .stack         0x80000 :
+    .stack (NOLOAD) :
     {
-        _stack = .;
-        *(.stack)
-    }
+        KEEP (*(.puf))
+        . = ALIGN(8);
+        _sstack = .;
+        KEEP (*(.isr_stack))
+        . = ALIGN(8);
+        _estack = .;
+    } > ram
+
+    /* heap section */
+    . = ALIGN(4);
+    .heap (NOLOAD) :
+    {
+        _sheap = . ;
+        _eheap = ORIGIN(ram) + LENGTH(ram) ;
+    } > ram
+
     /* Stabs debugging sections.  */
     .stab          0 : { *(.stab) }
     .stabstr       0 : { *(.stabstr) }
@@ -248,4 +273,8 @@ SECTIONS
     .ARM.attributes 0 : { KEEP (*(.ARM.attributes)) KEEP (*(.gnu.attributes)) }
     .note.gnu.arm.ident 0 : { KEEP (*(.note.gnu.arm.ident)) }
     /DISCARD/ : { *(.note.GNU-stack) *(.gnu_debuglink) *(.gnu.lto_*) }
+
+    /* Populate information about ram size */
+    _sram = ORIGIN(ram);
+    _eram = ORIGIN(ram) + LENGTH(ram);
 }
diff --git a/cpu/cortexm_common/vectors_cortexm.c b/cpu/cortexm_common/vectors_cortexm.c
index 25b9cf18cbc5..0d5766c24463 100644
--- a/cpu/cortexm_common/vectors_cortexm.c
+++ b/cpu/cortexm_common/vectors_cortexm.c
@@ -43,11 +43,10 @@
  * @brief   Memory markers, defined in the linker script
  * @{
  */
-extern uint32_t _sfixed;
-extern uint32_t _efixed;
 extern uint32_t _etext;
-extern uint32_t _srelocate;
-extern uint32_t _erelocate;
+extern uint32_t __data_start;
+extern uint32_t __data_end;
+extern uint32_t __data_load_start;
 extern uint32_t _szero;
 extern uint32_t _ezero;
 extern uint32_t _sstack;
@@ -78,7 +77,6 @@ __attribute__((weak)) void post_startup (void)
 void reset_handler_default(void)
 {
     uint32_t *dst;
-    uint32_t *src = &_etext;
 
 #ifdef MODULE_PUF_SRAM
     puf_sram_init((uint8_t *)&_srelocate, SEED_RAM_LEN);
@@ -98,12 +96,13 @@ void reset_handler_default(void)
 #endif
 
     /* load data section from flash to ram */
-    for (dst = &_srelocate; dst < &_erelocate; ) {
+    uint32_t *src = &__data_load_start;
+    for (dst = &__data_start; dst < &__data_end; ) {
         *(dst++) = *(src++);
     }
     /* default bss section to zero */
-    for (dst = &_szero; dst < &_ezero; ) {
-        *(dst++) = 0;
+    for (dst = &_szero; dst < &_ezero; ++dst) {
+        *dst = 0;
     }
 
 #ifdef MODULE_MPU_STACK_GUARD

From 1a4b90611871dff55e51aa9f6b711a36e0adeb8f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 06:35:43 +0200
Subject: [PATCH 04/27] fixup! cortexm_common: Update ldscript to be more
 similar to binutils default

---
 cpu/cortexm_common/ldscripts/cortexm_base.ld | 7 +++----
 cpu/cortexm_common/vectors_cortexm.c         | 6 +++---
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/cpu/cortexm_common/ldscripts/cortexm_base.ld b/cpu/cortexm_common/ldscripts/cortexm_base.ld
index 573b432497ce..c638bee1cdc0 100644
--- a/cpu/cortexm_common/ldscripts/cortexm_base.ld
+++ b/cpu/cortexm_common/ldscripts/cortexm_base.ld
@@ -201,16 +201,15 @@ SECTIONS
     _edata = .; PROVIDE (edata = .);
     .bss (NOLOAD)   :
     {
-      _szero = .;
-      __bss_start = .;
-      __bss_start__ = .;
+        __bss_start = .;
+        __bss_start__ = .;
         *(.dynbss)
         *(.bss .bss.* .gnu.linkonce.b.*)
         *(COMMON)
     } > ram
     . = ALIGN(32 / 8);
     _bss_end__ = . ; __bss_end__ = . ;
-    _ezero = .;
+    __bss_end = .;
     __end__ = . ;
     _end = .; PROVIDE (end = .);
     .stack (NOLOAD) :
diff --git a/cpu/cortexm_common/vectors_cortexm.c b/cpu/cortexm_common/vectors_cortexm.c
index 0d5766c24463..9773cdc370d3 100644
--- a/cpu/cortexm_common/vectors_cortexm.c
+++ b/cpu/cortexm_common/vectors_cortexm.c
@@ -47,8 +47,8 @@ extern uint32_t _etext;
 extern uint32_t __data_start;
 extern uint32_t __data_end;
 extern uint32_t __data_load_start;
-extern uint32_t _szero;
-extern uint32_t _ezero;
+extern uint32_t __bss_start;
+extern uint32_t __bss_end;
 extern uint32_t _sstack;
 extern uint32_t _estack;
 extern uint8_t _sram;
@@ -101,7 +101,7 @@ void reset_handler_default(void)
         *(dst++) = *(src++);
     }
     /* default bss section to zero */
-    for (dst = &_szero; dst < &_ezero; ++dst) {
+    for (dst = &__bss_start; dst < &__bss_end; ++dst) {
         *dst = 0;
     }
 

From 39d5d19552d2abfa22893cc4fd8890090322d8dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 06:51:50 +0200
Subject: [PATCH 05/27] kinetis: Adjust ldscript memory segment attributes

---
 cpu/kinetis/ldscripts/kinetis.ld | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cpu/kinetis/ldscripts/kinetis.ld b/cpu/kinetis/ldscripts/kinetis.ld
index 21f62364ea46..69afef317c45 100644
--- a/cpu/kinetis/ldscripts/kinetis.ld
+++ b/cpu/kinetis/ldscripts/kinetis.ld
@@ -30,7 +30,7 @@ MEMORY
     vectors    : ORIGIN = _rom_start_addr, LENGTH = _vectors_length
     flashsec   : ORIGIN = _rom_start_addr + _vectors_length, LENGTH = _flashsec_length
     rom (rx)   : ORIGIN = _rom_start_addr + _vectors_length + _flashsec_length, LENGTH = _rom_length - (_vectors_length + _flashsec_length)
-    ram (!rx)  : ORIGIN = _ram_start_addr, LENGTH = _ram_length
+    ram (w!rx) : ORIGIN = _ram_start_addr, LENGTH = _ram_length
 }
 
 SECTIONS

From a7f11256ae3287fed425ef19b7cb4af4239093c1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 06:57:46 +0200
Subject: [PATCH 06/27] fixup! fixup! cortexm_common: Update ldscript to be
 more similar to binutils default

---
 cpu/cortexm_common/ldscripts/cortexm_base.ld | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/cpu/cortexm_common/ldscripts/cortexm_base.ld b/cpu/cortexm_common/ldscripts/cortexm_base.ld
index c638bee1cdc0..25d687f8df63 100644
--- a/cpu/cortexm_common/ldscripts/cortexm_base.ld
+++ b/cpu/cortexm_common/ldscripts/cortexm_base.ld
@@ -206,7 +206,7 @@ SECTIONS
         *(.dynbss)
         *(.bss .bss.* .gnu.linkonce.b.*)
         *(COMMON)
-    } > ram
+    }
     . = ALIGN(32 / 8);
     _bss_end__ = . ; __bss_end__ = . ;
     __bss_end = .;
@@ -220,7 +220,7 @@ SECTIONS
         KEEP (*(.isr_stack))
         . = ALIGN(8);
         _estack = .;
-    } > ram
+    }
 
     /* heap section */
     . = ALIGN(4);
@@ -228,7 +228,7 @@ SECTIONS
     {
         _sheap = . ;
         _eheap = ORIGIN(ram) + LENGTH(ram) ;
-    } > ram
+    }
 
     /* Stabs debugging sections.  */
     .stab          0 : { *(.stab) }

From f73aead0ce4c000a9a4fec638494956876a7b686 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 12:46:00 +0200
Subject: [PATCH 07/27] fixup! fixup! fixup! cortexm_common: Update ldscript to
 be more similar to binutils default

---
 cpu/cortexm_common/ldscripts/cortexm_base.ld | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/cpu/cortexm_common/ldscripts/cortexm_base.ld b/cpu/cortexm_common/ldscripts/cortexm_base.ld
index 25d687f8df63..e94fff2ae732 100644
--- a/cpu/cortexm_common/ldscripts/cortexm_base.ld
+++ b/cpu/cortexm_common/ldscripts/cortexm_base.ld
@@ -173,10 +173,14 @@ SECTIONS
     .data.rel.ro    : { *(.data.rel.ro.local* .gnu.linkonce.d.rel.ro.local.*) *(.data.rel.ro .data.rel.ro.* .gnu.linkonce.d.rel.ro.*) }
     .dynamic        : { *(.dynamic) }
     .got            : { *(.got.plt) *(.igot.plt) *(.got) *(.igot) }
+    /* The relocation code assumes that the addresses are aligned in both ROM and RAM,
+     * This alignment section ensures that the LMA is aligned (ROM address) */
+    .romalign (NOLOAD) : { . = ALIGN(4); } > rom
 
     /* Writable sections, must be relocated from ROM to RAM during early boot */
     .data           :
     {
+        . = ALIGN(4);
         __data_start = .;
         *(.data .data.* .gnu.linkonce.d.*)
         SORT(CONSTRUCTORS)
@@ -184,6 +188,7 @@ SECTIONS
     __data_load_start = LOADADDR(.data);
     .ramfunc        :
     {
+        . = ALIGN(4);
         __ramfunc_start = .;
         *(.ramfunc .ramfunc.*)
     } > ram AT> rom
@@ -201,6 +206,7 @@ SECTIONS
     _edata = .; PROVIDE (edata = .);
     .bss (NOLOAD)   :
     {
+        . = ALIGN(4);
         __bss_start = .;
         __bss_start__ = .;
         *(.dynbss)

From fddad1f989a54bc651c790cf2cec564c87d707b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 12:57:58 +0200
Subject: [PATCH 08/27] fixup! fixup! fixup! fixup! cortexm_common: Update
 ldscript to be more similar to binutils default

---
 cpu/cortexm_common/ldscripts/cortexm_base.ld | 32 +++++++++++++++++---
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/cpu/cortexm_common/ldscripts/cortexm_base.ld b/cpu/cortexm_common/ldscripts/cortexm_base.ld
index e94fff2ae732..8363727e515c 100644
--- a/cpu/cortexm_common/ldscripts/cortexm_base.ld
+++ b/cpu/cortexm_common/ldscripts/cortexm_base.ld
@@ -22,6 +22,7 @@ SECTIONS
     {
         _isr_vectors = DEFINED(_isr_vectors) ? _isr_vectors : . ;
         KEEP(*(SORT(.vectors*)))
+        . = ALIGN(4);
     }
     .interp         : { *(.interp) }
     .note.gnu.build-id : { *(.note.gnu.build-id) }
@@ -83,6 +84,7 @@ SECTIONS
     .iplt           : { *(.iplt) }
     .text           :
     {
+        . = ALIGN(4);
         *(.text.unlikely .text.*_unlikely .text.unlikely.*)
         *(.text.exit .text.exit.*)
         *(.text.startup .text.startup.*)
@@ -91,7 +93,9 @@ SECTIONS
         /* .gnu.warning sections are handled specially by elf32.em.  */
         *(.gnu.warning)
         *(.glue_7t) *(.glue_7) *(.vfp11_veneer) *(.v4_bx)
+        . = ALIGN(4);
     }
+    . = ALIGN(4);
     .fini           :
     {
         KEEP (*(SORT_NONE(.fini)))
@@ -99,8 +103,20 @@ SECTIONS
     PROVIDE (__etext = .);
     PROVIDE (_etext = .);
     PROVIDE (etext = .);
-    .rodata         : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
-    .rodata1        : { *(.rodata1) }
+    .rodata         :
+    {
+        . = ALIGN(4);
+        *(.rodata .rodata.* .gnu.linkonce.r.*)
+        . = ALIGN(4);
+    }
+    . = ALIGN(4);
+    .rodata1        :
+    {
+        . = ALIGN(4);
+        *(.rodata1)
+        . = ALIGN(4);
+    }
+    . = ALIGN(4);
     .openocd        :
     {
         KEEP (*(.openocd .openocd.*))
@@ -122,23 +138,29 @@ SECTIONS
      * saves RAM space. */
     .preinit_array  :
     {
+        . = ALIGN(4);
         PROVIDE_HIDDEN (__preinit_array_start = .);
         KEEP (*(.preinit_array))
         PROVIDE_HIDDEN (__preinit_array_end = .);
+        . = ALIGN(4);
     } > rom
     .init_array     :
     {
+        . = ALIGN(4);
         PROVIDE_HIDDEN (__init_array_start = .);
         KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
         KEEP (*(.init_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .ctors))
         PROVIDE_HIDDEN (__init_array_end = .);
+        . = ALIGN(4);
     } > rom
     .fini_array     :
     {
+        . = ALIGN(4);
         PROVIDE_HIDDEN (__fini_array_start = .);
         KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))
         KEEP (*(.fini_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .dtors))
         PROVIDE_HIDDEN (__fini_array_end = .);
+        . = ALIGN(4);
     } > rom
     .ctors          :
     {
@@ -173,9 +195,6 @@ SECTIONS
     .data.rel.ro    : { *(.data.rel.ro.local* .gnu.linkonce.d.rel.ro.local.*) *(.data.rel.ro .data.rel.ro.* .gnu.linkonce.d.rel.ro.*) }
     .dynamic        : { *(.dynamic) }
     .got            : { *(.got.plt) *(.igot.plt) *(.got) *(.igot) }
-    /* The relocation code assumes that the addresses are aligned in both ROM and RAM,
-     * This alignment section ensures that the LMA is aligned (ROM address) */
-    .romalign (NOLOAD) : { . = ALIGN(4); } > rom
 
     /* Writable sections, must be relocated from ROM to RAM during early boot */
     .data           :
@@ -184,6 +203,7 @@ SECTIONS
         __data_start = .;
         *(.data .data.* .gnu.linkonce.d.*)
         SORT(CONSTRUCTORS)
+        . = ALIGN(4);
     } > ram AT> rom
     __data_load_start = LOADADDR(.data);
     .ramfunc        :
@@ -191,6 +211,7 @@ SECTIONS
         . = ALIGN(4);
         __ramfunc_start = .;
         *(.ramfunc .ramfunc.*)
+        . = ALIGN(4);
     } > ram AT> rom
     __ramfunc_end = .;
     /* Exception handling  */
@@ -212,6 +233,7 @@ SECTIONS
         *(.dynbss)
         *(.bss .bss.* .gnu.linkonce.b.*)
         *(COMMON)
+        . = ALIGN(4);
     }
     . = ALIGN(32 / 8);
     _bss_end__ = . ; __bss_end__ = . ;

From 0688e88b1faaae5e16ccccfeda0992bbe4473639 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Sat, 25 Aug 2018 14:49:30 +0200
Subject: [PATCH 09/27] squash fix puf_sram init on cortex-m

---
 cpu/cortexm_common/vectors_cortexm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cpu/cortexm_common/vectors_cortexm.c b/cpu/cortexm_common/vectors_cortexm.c
index 9773cdc370d3..6c8c069566bd 100644
--- a/cpu/cortexm_common/vectors_cortexm.c
+++ b/cpu/cortexm_common/vectors_cortexm.c
@@ -79,7 +79,7 @@ void reset_handler_default(void)
     uint32_t *dst;
 
 #ifdef MODULE_PUF_SRAM
-    puf_sram_init((uint8_t *)&_srelocate, SEED_RAM_LEN);
+    puf_sram_init((uint8_t *)&__data_start, SEED_RAM_LEN);
 #endif
 
     pre_startup();

From ed277c687cd7689a652276df8fd0318603ca880b Mon Sep 17 00:00:00 2001
From: Kaspar Schleiser <kaspar@schleiser.de>
Date: Fri, 4 May 2018 09:41:53 +0200
Subject: [PATCH 10/27] core: Introduce cross file arrays (XFA)

---
 core/include/xfa.h | 101 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 101 insertions(+)
 create mode 100644 core/include/xfa.h

diff --git a/core/include/xfa.h b/core/include/xfa.h
new file mode 100644
index 000000000000..aad6729dbe79
--- /dev/null
+++ b/core/include/xfa.h
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2016 Kaspar Schleiser <kaspar@schleiser.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     core_util
+ * @brief       Cross File Arrays
+ * @{
+ *
+ * This macro, in combination with an entry in the linker scripts, allows the
+ * definition of constant arrays to be spread over multiple C compilation
+ * units. These arrays are called "cross-file arrays" or short xfa.
+ *
+ *
+ *
+ * @file
+ * @author      Kaspar Schleiser <kaspar@schleiser.de>
+ */
+
+#ifndef XFA_H
+#define XFA_H
+
+/**
+ * @brief helper macro for other XFA_* macros
+ *
+ * @internal
+ */
+#define _XFA(name, prio) __attribute__((used, section(".xfa." #name "." #prio)))
+
+/**
+ * @brief Define a cross-file array
+ *
+ * This macro defines the symbols necessary to use XFA_START() and XFA_END().
+ * It needs to be part of one single compilation unit.
+ *
+ * @param[in]   type    name of the cross-file array
+ * @param[in]   name    name of the cross-file array
+ */
+#define XFA_INIT(type, name) \
+    _Pragma("GCC diagnostic push") \
+    _Pragma("GCC diagnostic ignored \"-Wpedantic\"") \
+    const _XFA(name, 0_) type name [0] = {}; \
+    const _XFA(name, 9_) type name ## _end [0] = {}; \
+    _Pragma("GCC diagnostic pop") \
+    extern unsigned __xfa_dummy
+
+/**
+ * @brief Declare an external cross-file array
+ *
+ * This macro defines the symbols necessary to use XFA_START() and XFA_END().
+ * Think of this as XFA_INIT() but with "extern" keyword.
+ * It is supposed to be used in compilation units where the cross file array is
+ * being accessed, but not defined using XFA_INIT.
+ *
+ * @param[in]   type    name of the cross-file array
+ * @param[in]   name    name of the cross-file array
+ */
+#define XFA_USE(type, name) \
+    extern const type name [0]; \
+    extern const type name ## _end [0];
+
+/**
+ * @brief Define variable in cross-file array
+ *
+ * Variables will end up sorted by prio.
+ *
+ * Add this to the type in a variable definition, e.g.:
+ *
+ *     XFA(driver_params, 0) driver_params_t _onboard = { .pin=42 };
+ *
+ * @param[in]   name    name of the xfa
+ * @param[in]   prio    priority within the xfa
+ */
+#define XFA(xfa_name, prio) _XFA(xfa_name, 5_ ##prio)
+
+/**
+ * @brief Add a pointer to cross-file array
+ *
+ * Pointers will end up sorted by prio.
+ *
+ * @param[in]   xfa_name    name of the xfa
+ * @param[in]   prio        priority within the xfa
+ * @param[in]   name        symbol name
+ * @param[in]   entry       pointer variable to add to xfa
+ */
+#define XFA_ADD_PTR(xfa_name, prio, name, entry) \
+    _XFA(xfa_name, 5_ ##prio) \
+    const typeof(entry) xfa_name ## _ ## prio ## _ ## name = entry
+
+/**
+ * @brief Calculate number of entries in cross-file array
+ *
+ */
+#define XFA_LEN(type, name) (((char*)name ## _end - (char*)name)/sizeof(type))
+
+/** @} */
+#endif /* XFA_H */

From eb933cd171574e9a79737338378cd00f08b42e94 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Fri, 4 May 2018 06:11:51 +0200
Subject: [PATCH 11/27] squash XFA_CONST

---
 core/include/xfa.h | 70 ++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 61 insertions(+), 9 deletions(-)

diff --git a/core/include/xfa.h b/core/include/xfa.h
index aad6729dbe79..5fe1892c3aaf 100644
--- a/core/include/xfa.h
+++ b/core/include/xfa.h
@@ -32,7 +32,31 @@
 #define _XFA(name, prio) __attribute__((used, section(".xfa." #name "." #prio)))
 
 /**
- * @brief Define a cross-file array
+ * @brief helper macro for other XFA_* macros
+ *
+ * @internal
+ */
+#define _XFA_CONST(name, prio) __attribute__((used, section(".roxfa." #name "." #prio)))
+
+/**
+ * @brief Define a read-only cross-file array
+ *
+ * This macro defines the symbols necessary to use XFA_START() and XFA_END().
+ * It needs to be part of one single compilation unit.
+ *
+ * @param[in]   type    name of the cross-file array
+ * @param[in]   name    name of the cross-file array
+ */
+#define XFA_INIT_CONST(type, name) \
+    _Pragma("GCC diagnostic push") \
+    _Pragma("GCC diagnostic ignored \"-Wpedantic\"") \
+    const _XFA_CONST(name, 0_) type name [0] = {}; \
+    const _XFA_CONST(name, 9_) type name ## _end [0] = {}; \
+    _Pragma("GCC diagnostic pop") \
+    extern unsigned __xfa_dummy
+
+/**
+ * @brief Define a writable cross-file array
  *
  * This macro defines the symbols necessary to use XFA_START() and XFA_END().
  * It needs to be part of one single compilation unit.
@@ -43,13 +67,13 @@
 #define XFA_INIT(type, name) \
     _Pragma("GCC diagnostic push") \
     _Pragma("GCC diagnostic ignored \"-Wpedantic\"") \
-    const _XFA(name, 0_) type name [0] = {}; \
-    const _XFA(name, 9_) type name ## _end [0] = {}; \
+    _XFA(name, 0_) type name [0] = {}; \
+    _XFA(name, 9_) type name ## _end [0] = {}; \
     _Pragma("GCC diagnostic pop") \
     extern unsigned __xfa_dummy
 
 /**
- * @brief Declare an external cross-file array
+ * @brief Declare an external read-only cross-file array
  *
  * This macro defines the symbols necessary to use XFA_START() and XFA_END().
  * Think of this as XFA_INIT() but with "extern" keyword.
@@ -59,12 +83,27 @@
  * @param[in]   type    name of the cross-file array
  * @param[in]   name    name of the cross-file array
  */
-#define XFA_USE(type, name) \
+#define XFA_USE_CONST(type, name) \
     extern const type name [0]; \
     extern const type name ## _end [0];
 
 /**
- * @brief Define variable in cross-file array
+ * @brief Declare an external writable cross-file array
+ *
+ * This macro defines the symbols necessary to use XFA_START() and XFA_END().
+ * Think of this as XFA_INIT() but with "extern" keyword.
+ * It is supposed to be used in compilation units where the cross file array is
+ * being accessed, but not defined using XFA_INIT.
+ *
+ * @param[in]   type    name of the cross-file array
+ * @param[in]   name    name of the cross-file array
+ */
+#define XFA_USE(type, name) \
+    extern type name [0]; \
+    extern type name ## _end [0];
+
+/**
+ * @brief Define variable in writable cross-file array
  *
  * Variables will end up sorted by prio.
  *
@@ -77,6 +116,20 @@
  */
 #define XFA(xfa_name, prio) _XFA(xfa_name, 5_ ##prio)
 
+/**
+ * @brief Define variable in read-only cross-file array
+ *
+ * Variables will end up sorted by prio.
+ *
+ * Add this to the type in a variable definition, e.g.:
+ *
+ *     XFA(driver_params, 0) driver_params_t _onboard = { .pin=42 };
+ *
+ * @param[in]   name    name of the xfa
+ * @param[in]   prio    priority within the xfa
+ */
+#define XFA_CONST(xfa_name, prio) _XFA_CONST(xfa_name, 5_ ##prio)
+
 /**
  * @brief Add a pointer to cross-file array
  *
@@ -88,14 +141,13 @@
  * @param[in]   entry       pointer variable to add to xfa
  */
 #define XFA_ADD_PTR(xfa_name, prio, name, entry) \
-    _XFA(xfa_name, 5_ ##prio) \
+    _XFA_CONST(xfa_name, 5_ ##prio) \
     const typeof(entry) xfa_name ## _ ## prio ## _ ## name = entry
 
 /**
  * @brief Calculate number of entries in cross-file array
- *
  */
-#define XFA_LEN(type, name) (((char*)name ## _end - (char*)name)/sizeof(type))
+#define XFA_LEN(type, name) (((const char*)name ## _end - (const char*)name) / sizeof(type))
 
 /** @} */
 #endif /* XFA_H */

From 21b36b36697751200261c4d9131b0821bf5ff4cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Tue, 8 May 2018 16:11:12 +0200
Subject: [PATCH 12/27] fixup! squash XFA_CONST

---
 core/include/xfa.h    | 10 +++++-----
 core/ldscripts/xfa.ld | 23 +++++++++++++++++++++++
 2 files changed, 28 insertions(+), 5 deletions(-)
 create mode 100644 core/ldscripts/xfa.ld

diff --git a/core/include/xfa.h b/core/include/xfa.h
index 5fe1892c3aaf..0ee9cd86d457 100644
--- a/core/include/xfa.h
+++ b/core/include/xfa.h
@@ -36,7 +36,7 @@
  *
  * @internal
  */
-#define _XFA_CONST(name, prio) __attribute__((used, section(".roxfa." #name "." #prio)))
+#define _XFA_CONST(name, prio) __attribute__((used, section(".roxfa." #name "." #prio))) const
 
 /**
  * @brief Define a read-only cross-file array
@@ -50,10 +50,10 @@
 #define XFA_INIT_CONST(type, name) \
     _Pragma("GCC diagnostic push") \
     _Pragma("GCC diagnostic ignored \"-Wpedantic\"") \
-    const _XFA_CONST(name, 0_) type name [0] = {}; \
-    const _XFA_CONST(name, 9_) type name ## _end [0] = {}; \
+    _XFA_CONST(name, 0_) const type name [0] = {}; \
+    _XFA_CONST(name, 9_) const type name ## _end [0] = {}; \
     _Pragma("GCC diagnostic pop") \
-    extern unsigned __xfa_dummy
+    extern const unsigned __xfa_dummy
 
 /**
  * @brief Define a writable cross-file array
@@ -70,7 +70,7 @@
     _XFA(name, 0_) type name [0] = {}; \
     _XFA(name, 9_) type name ## _end [0] = {}; \
     _Pragma("GCC diagnostic pop") \
-    extern unsigned __xfa_dummy
+    extern const unsigned __xfa_dummy
 
 /**
  * @brief Declare an external read-only cross-file array
diff --git a/core/ldscripts/xfa.ld b/core/ldscripts/xfa.ld
new file mode 100644
index 000000000000..34b7d7635fe0
--- /dev/null
+++ b/core/ldscripts/xfa.ld
@@ -0,0 +1,23 @@
+SECTIONS
+{
+    .data :
+    {
+        KEEP (*(SORT(.xfa.*)))
+    }
+    __data_start = ADDR(.data);
+    __data_load_start = LOADADDR(.data);
+    __data_end = (__data_start + SIZEOF(.data));
+    __data_load_end = (__data_load_start + SIZEOF(.data));
+}
+
+INSERT AFTER .text;
+
+SECTIONS
+{
+    .rodata :
+    {
+        KEEP (*(SORT(.roxfa.*)))
+    }
+}
+
+INSERT AFTER .text;

From ecc4d74a5a8afe9c673b6c28a19ec366b3757017 Mon Sep 17 00:00:00 2001
From: Kaspar Schleiser <kaspar@schleiser.de>
Date: Thu, 22 Sep 2016 13:09:58 +0200
Subject: [PATCH 13/27] cpu: native: add xfa ld script

---
 cpu/native/Makefile.include | 2 ++
 cpu/native/ldscripts/xfa.ld | 9 +++++++++
 2 files changed, 11 insertions(+)
 create mode 100644 cpu/native/ldscripts/xfa.ld

diff --git a/cpu/native/Makefile.include b/cpu/native/Makefile.include
index 76ddd9ead04c..6ef09a07af6c 100644
--- a/cpu/native/Makefile.include
+++ b/cpu/native/Makefile.include
@@ -8,6 +8,8 @@ endif
 USEMODULE += periph
 USEMODULE += periph_uart
 
+LINKFLAGS += -T$(RIOTCPU)/native/ldscripts/xfa.ld
+
 # include common peripheral initialization
 USEMODULE += periph_common
 
diff --git a/cpu/native/ldscripts/xfa.ld b/cpu/native/ldscripts/xfa.ld
new file mode 100644
index 000000000000..17e507b72c7f
--- /dev/null
+++ b/cpu/native/ldscripts/xfa.ld
@@ -0,0 +1,9 @@
+SECTIONS
+{
+      .xfa     :
+      {
+          KEEP (*(SORT(.xfa.*)))
+      }
+}
+
+INSERT AFTER .init;

From a029359ea5a8e2f0145298704b57263f8b39224e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Sun, 6 May 2018 07:15:55 +0200
Subject: [PATCH 14/27] squash native XFA const

---
 cpu/native/ldscripts/xfa.ld | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/cpu/native/ldscripts/xfa.ld b/cpu/native/ldscripts/xfa.ld
index 17e507b72c7f..4e7dd99ff031 100644
--- a/cpu/native/ldscripts/xfa.ld
+++ b/cpu/native/ldscripts/xfa.ld
@@ -1,9 +1,19 @@
 SECTIONS
 {
-      .xfa     :
-      {
-          KEEP (*(SORT(.xfa.*)))
-      }
+    .xfa     :
+    {
+        KEEP (*(SORT(.xfa.*)))
+    }
 }
 
-INSERT AFTER .init;
+INSERT AFTER .data;
+
+SECTIONS
+{
+    .roxfa     :
+    {
+        KEEP (*(SORT(.roxfa.*)))
+    }
+}
+
+INSERT AFTER .rodata;

From 306f9599b420aa80918efb4c3983b0b1ce0458ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Tue, 8 May 2018 16:13:04 +0200
Subject: [PATCH 15/27] squash XFA use global ldscript for XFA

---
 Makefile.include            |  5 +++++
 cpu/native/Makefile.include |  2 --
 cpu/native/ldscripts/xfa.ld | 19 -------------------
 3 files changed, 5 insertions(+), 21 deletions(-)
 delete mode 100644 cpu/native/ldscripts/xfa.ld

diff --git a/Makefile.include b/Makefile.include
index 06ca9e5b6e2f..888341469b04 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -233,6 +233,11 @@ export PREFIX ?= $(if $(TARGET_ARCH),$(TARGET_ARCH)-)
 # Add standard include directories
 INCLUDES += -I$(RIOTBASE)/core/include -I$(RIOTBASE)/drivers/include -I$(RIOTBASE)/sys/include
 
+# Augmentation ldscript for cross file arrays (XFA)
+# this argument must come before any other -T options on the command line,
+# otherwise we get an error message ".text not found for insert"
+export LINKFLAGS += -T$(RIOTBASE)/core/ldscripts/xfa.ld
+
 # process provided features
 -include $(RIOTBOARD)/$(BOARD)/Makefile.features
 
diff --git a/cpu/native/Makefile.include b/cpu/native/Makefile.include
index 6ef09a07af6c..76ddd9ead04c 100644
--- a/cpu/native/Makefile.include
+++ b/cpu/native/Makefile.include
@@ -8,8 +8,6 @@ endif
 USEMODULE += periph
 USEMODULE += periph_uart
 
-LINKFLAGS += -T$(RIOTCPU)/native/ldscripts/xfa.ld
-
 # include common peripheral initialization
 USEMODULE += periph_common
 
diff --git a/cpu/native/ldscripts/xfa.ld b/cpu/native/ldscripts/xfa.ld
deleted file mode 100644
index 4e7dd99ff031..000000000000
--- a/cpu/native/ldscripts/xfa.ld
+++ /dev/null
@@ -1,19 +0,0 @@
-SECTIONS
-{
-    .xfa     :
-    {
-        KEEP (*(SORT(.xfa.*)))
-    }
-}
-
-INSERT AFTER .data;
-
-SECTIONS
-{
-    .roxfa     :
-    {
-        KEEP (*(SORT(.roxfa.*)))
-    }
-}
-
-INSERT AFTER .rodata;

From ede64a198a53e400b9aee2ef7cd297acc7782c8c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Sun, 6 May 2018 07:15:17 +0200
Subject: [PATCH 16/27] tests: Add xfa test

---
 tests/xfa/Makefile   |  5 +++++
 tests/xfa/main.c     | 44 ++++++++++++++++++++++++++++++++++++++++++++
 tests/xfa/xfatest.h  |  9 +++++++++
 tests/xfa/xfatest1.c |  6 ++++++
 tests/xfa/xfatest2.c |  6 ++++++
 5 files changed, 70 insertions(+)
 create mode 100644 tests/xfa/Makefile
 create mode 100644 tests/xfa/main.c
 create mode 100644 tests/xfa/xfatest.h
 create mode 100644 tests/xfa/xfatest1.c
 create mode 100644 tests/xfa/xfatest2.c

diff --git a/tests/xfa/Makefile b/tests/xfa/Makefile
new file mode 100644
index 000000000000..abe5a68a5500
--- /dev/null
+++ b/tests/xfa/Makefile
@@ -0,0 +1,5 @@
+# name of your application
+APPLICATION = xfa
+include ../Makefile.tests_common
+
+include $(RIOTBASE)/Makefile.include
diff --git a/tests/xfa/main.c b/tests/xfa/main.c
new file mode 100644
index 000000000000..7f98fda88177
--- /dev/null
+++ b/tests/xfa/main.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2015 Kaspar Schleiser <kaspar@schleiser.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     test
+ * @{
+ *
+ * @file
+ * @brief       cross file array (XFA) test application
+ *
+ * @author      Kaspar Schleiser <kaspar@schleiser.de>
+ *
+ * @}
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+
+#include "xfa.h"
+
+#include "xfatest.h"
+
+XFA_INIT(xfatest_t, xfatest);
+
+/* hack to force inclusion of otherwise unused compilation units */
+extern int hack1;
+extern int hack2;
+
+int main(void)
+{
+    unsigned n = XFA_LEN(xfatest_t, xfatest);
+    for (unsigned i = 0; i < n; i++) {
+        printf("%u %s\n", xfatest[i].val, xfatest[i].text);
+    }
+
+    hack1 = hack2;
+
+    return 0;
+}
diff --git a/tests/xfa/xfatest.h b/tests/xfa/xfatest.h
new file mode 100644
index 000000000000..1511a80e93e3
--- /dev/null
+++ b/tests/xfa/xfatest.h
@@ -0,0 +1,9 @@
+#ifndef XFATEST_H
+#define XFATEST_H
+
+typedef struct {
+    unsigned val;
+    const char *text;
+} xfatest_t;
+
+#endif /* XFATEST_H */
diff --git a/tests/xfa/xfatest1.c b/tests/xfa/xfatest1.c
new file mode 100644
index 000000000000..5c92085cf04b
--- /dev/null
+++ b/tests/xfa/xfatest1.c
@@ -0,0 +1,6 @@
+#include "xfa.h"
+#include "xfatest.h"
+
+XFA(xfatest, 0) xfatest_t _xfatest1 = { .val = 1, .text = "xfatest1" };
+
+int hack1;
diff --git a/tests/xfa/xfatest2.c b/tests/xfa/xfatest2.c
new file mode 100644
index 000000000000..a7378a3457c7
--- /dev/null
+++ b/tests/xfa/xfatest2.c
@@ -0,0 +1,6 @@
+#include "xfa.h"
+#include "xfatest.h"
+
+XFA(xfatest, 0) xfatest_t _xfatest2 = { .val = 2, .text = "xfatest2" };
+
+int hack2;

From ec15abe79ef21d4dd07d3e81db1f8512168c9b25 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Tue, 8 May 2018 16:12:26 +0200
Subject: [PATCH 17/27] squash xfa add const test

---
 tests/xfa/main.c     | 9 ++++++++-
 tests/xfa/xfatest1.c | 1 +
 tests/xfa/xfatest2.c | 1 +
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/tests/xfa/main.c b/tests/xfa/main.c
index 7f98fda88177..3143bc7a0938 100644
--- a/tests/xfa/main.c
+++ b/tests/xfa/main.c
@@ -26,6 +26,7 @@
 #include "xfatest.h"
 
 XFA_INIT(xfatest_t, xfatest);
+XFA_INIT_CONST(xfatest_t, xfatest_const);
 
 /* hack to force inclusion of otherwise unused compilation units */
 extern int hack1;
@@ -33,9 +34,15 @@ extern int hack2;
 
 int main(void)
 {
+    puts("Cross file array test");
+
     unsigned n = XFA_LEN(xfatest_t, xfatest);
     for (unsigned i = 0; i < n; i++) {
-        printf("%u %s\n", xfatest[i].val, xfatest[i].text);
+        printf("(%u/%u): %u, \"%s\"\n", i, n, xfatest[i].val, xfatest[i].text);
+    }
+    n = XFA_LEN(xfatest_t, xfatest_const);
+    for (unsigned i = 0; i < n; i++) {
+        printf("(%u/%u): %u, \"%s\"\n", i, n, xfatest_const[i].val, xfatest_const[i].text);
     }
 
     hack1 = hack2;
diff --git a/tests/xfa/xfatest1.c b/tests/xfa/xfatest1.c
index 5c92085cf04b..5b6ec26c39a0 100644
--- a/tests/xfa/xfatest1.c
+++ b/tests/xfa/xfatest1.c
@@ -2,5 +2,6 @@
 #include "xfatest.h"
 
 XFA(xfatest, 0) xfatest_t _xfatest1 = { .val = 1, .text = "xfatest1" };
+XFA_CONST(xfatest_const, 0) xfatest_t _xfatest_const1 = { .val = 123, .text = "xfatest_const1" };
 
 int hack1;
diff --git a/tests/xfa/xfatest2.c b/tests/xfa/xfatest2.c
index a7378a3457c7..622967efce63 100644
--- a/tests/xfa/xfatest2.c
+++ b/tests/xfa/xfatest2.c
@@ -2,5 +2,6 @@
 #include "xfatest.h"
 
 XFA(xfatest, 0) xfatest_t _xfatest2 = { .val = 2, .text = "xfatest2" };
+XFA_CONST(xfatest_const, 0) xfatest_t _xfatest_const2 = { .val = 45, .text = "xfatest_const2" };
 
 int hack2;

From b53ed6115564840aae00e36623ac0b8907c74c9f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 07:49:35 +0200
Subject: [PATCH 18/27] lpc2387: specify load segment instead of load address
 for .data

---
 cpu/lpc2387/ldscripts/lpc2387.ld | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/cpu/lpc2387/ldscripts/lpc2387.ld b/cpu/lpc2387/ldscripts/lpc2387.ld
index 2edb378dd3ea..2a9b0e839d5b 100644
--- a/cpu/lpc2387/ldscripts/lpc2387.ld
+++ b/cpu/lpc2387/ldscripts/lpc2387.ld
@@ -184,7 +184,7 @@ SECTIONS
      * collect all initialized .data sections that go into RAM
      * initial values get placed at the end of .text in flash
      */
-    .data : AT (_etext)
+    .data :
     {
         . = ALIGN(4);                   /* ensure data is aligned so relocation can use 4-byte operations */
         _data = .;                      /* create a global symbol marking the start of the .data section  */
@@ -209,7 +209,7 @@ SECTIONS
         KEEP(*(SORT(.fini_array.*)))
             KEEP(*(.fini_array))
             PROVIDE_HIDDEN (__fini_array_end = .);
-    } >ram                              /* put all the above into RAM (but load the LMA copy into FLASH) */
+    } > ram AT> flash                   /* put all the above into RAM (but load the LMA copy into FLASH) */
     . = ALIGN(4);                       /* ensure data is aligned so relocation can use 4-byte operations */
     _edata = .;                         /* define a global symbol marking the end of the .data section  */
 

From 2339ed35cef8381fbe1aefe813569a5db36c57cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 07:52:32 +0200
Subject: [PATCH 19/27] atmega_common: add arch specific XFA ldscript to
 properly place .roxfa

---
 cpu/atmega_common/Makefile.include |  1 +
 cpu/atmega_common/ldscripts/xfa.ld | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)
 create mode 100644 cpu/atmega_common/ldscripts/xfa.ld

diff --git a/cpu/atmega_common/Makefile.include b/cpu/atmega_common/Makefile.include
index 717ec08ab640..3e8c1a6ca686 100644
--- a/cpu/atmega_common/Makefile.include
+++ b/cpu/atmega_common/Makefile.include
@@ -8,6 +8,7 @@ export CFLAGS_OPT  ?= -Os
 
 export CFLAGS += $(CFLAGS_CPU) $(CFLAGS_LINK) $(CFLAGS_DBG) $(CFLAGS_OPT)
 export ASFLAGS += $(CFLAGS_CPU) $(CFLAGS_DBG)
+LINKFLAGS += -L$(RIOTCPU)/atmega_common/ldscripts
 export LINKFLAGS += $(CFLAGS_CPU) $(CFLAGS_DBG) $(CFLAGS_OPT) -static -lgcc -e reset_handler -Wl,--gc-sections
 
 # export the peripheral drivers to be linked into the final binary
diff --git a/cpu/atmega_common/ldscripts/xfa.ld b/cpu/atmega_common/ldscripts/xfa.ld
new file mode 100644
index 000000000000..29b85699c9a9
--- /dev/null
+++ b/cpu/atmega_common/ldscripts/xfa.ld
@@ -0,0 +1,16 @@
+SECTIONS
+{
+    .data :
+    {
+        /* Special case for AVR (Harvard architecture) where .rodata is merged
+         * into .data by the toolchain default ldscripts. */
+        KEEP (*(SORT(.roxfa.*)))
+        KEEP (*(SORT(.xfa.*)))
+    }
+    __data_start = ADDR(.data);
+    __data_load_start = LOADADDR(.data);
+    __data_end = (__data_start + SIZEOF(.data));
+    __data_load_end = (__data_load_start + SIZEOF(.data));
+}
+
+INSERT AFTER .text;

From fc08ca9426ed569d88ecd40148d2c8c22a29bf43 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 07:53:00 +0200
Subject: [PATCH 20/27] fixup! squash XFA use global ldscript for XFA

---
 Makefile.include | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Makefile.include b/Makefile.include
index 888341469b04..0aa8c48fb2c9 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -236,7 +236,7 @@ INCLUDES += -I$(RIOTBASE)/core/include -I$(RIOTBASE)/drivers/include -I$(RIOTBAS
 # Augmentation ldscript for cross file arrays (XFA)
 # this argument must come before any other -T options on the command line,
 # otherwise we get an error message ".text not found for insert"
-export LINKFLAGS += -T$(RIOTBASE)/core/ldscripts/xfa.ld
+LINKFLAGS += -Txfa.ld
 
 # process provided features
 -include $(RIOTBOARD)/$(BOARD)/Makefile.features
@@ -257,6 +257,10 @@ TOOLCHAINS_SUPPORTED ?= gnu
 # Import all toolchain settings
 include $(RIOTMAKE)/toolchain/$(TOOLCHAIN).inc.mk
 
+# Append ldscript path after importing CPU and board makefiles to allow
+# overriding the core ldscripts
+LINKFLAGS += -L$(RIOTBASE)/core/ldscripts
+
 # Tell ccache to pass the original file to the compiler, instead of passing the
 # preprocessed code. Without this setting, the compilation will fail with
 # -Wimplicit-fallthrough warnings even when the fall through case is properly

From 60c365b908df898e2c0c296aa82d834f283cc048 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Wed, 9 May 2018 08:25:50 +0200
Subject: [PATCH 21/27] fixup! squash xfa add const test

---
 tests/xfa/main.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/xfa/main.c b/tests/xfa/main.c
index 3143bc7a0938..d771850863d8 100644
--- a/tests/xfa/main.c
+++ b/tests/xfa/main.c
@@ -37,12 +37,14 @@ int main(void)
     puts("Cross file array test");
 
     unsigned n = XFA_LEN(xfatest_t, xfatest);
+    printf("xfatest[%u]:\n", n);
     for (unsigned i = 0; i < n; i++) {
-        printf("(%u/%u): %u, \"%s\"\n", i, n, xfatest[i].val, xfatest[i].text);
+        printf("[%u] = %u, \"%s\"\n", i, xfatest[i].val, xfatest[i].text);
     }
     n = XFA_LEN(xfatest_t, xfatest_const);
+    printf("xfatest_const[%u]:\n", n);
     for (unsigned i = 0; i < n; i++) {
-        printf("(%u/%u): %u, \"%s\"\n", i, n, xfatest_const[i].val, xfatest_const[i].text);
+        printf("[%u] = %u, \"%s\"\n", i, xfatest_const[i].val, xfatest_const[i].text);
     }
 
     hack1 = hack2;

From 81137b6af0cd1a7fe9dbcb015f2500ac36bf88ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 22:27:10 +0200
Subject: [PATCH 22/27] unittests: Add XFA tests

---
 .../tests-core/tests-core-xfa-data1.c         |  32 ++++
 .../tests-core/tests-core-xfa-data2.c         |  27 ++++
 tests/unittests/tests-core/tests-core-xfa.c   | 146 ++++++++++++++++++
 tests/unittests/tests-core/tests-core-xfa.h   |  28 ++++
 tests/unittests/tests-core/tests-core.c       |   1 +
 tests/unittests/tests-core/tests-core.h       |   7 +
 6 files changed, 241 insertions(+)
 create mode 100644 tests/unittests/tests-core/tests-core-xfa-data1.c
 create mode 100644 tests/unittests/tests-core/tests-core-xfa-data2.c
 create mode 100644 tests/unittests/tests-core/tests-core-xfa.c
 create mode 100644 tests/unittests/tests-core/tests-core-xfa.h

diff --git a/tests/unittests/tests-core/tests-core-xfa-data1.c b/tests/unittests/tests-core/tests-core-xfa-data1.c
new file mode 100644
index 000000000000..af8af9c07828
--- /dev/null
+++ b/tests/unittests/tests-core/tests-core-xfa-data1.c
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2018 Eistec AB
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @addtogroup  unittests
+ * @{
+ *
+ * @file
+ * @brief       Data elements for the core/xfa unit test
+ *
+ * @author      Joakim Nohlgård <joakim.nohlgard@eistec.se>
+ */
+#include "xfa.h"
+#include "tests-core-xfa.h"
+
+XFA(xfatest, 0) xfatest_t _xfatest1 = { .val = 12345, .text = "xfatest1" };
+XFA_CONST(xfatest_const, 0) xfatest_t _xfatest_const1 = { .val = 0xcafe, .text = "xfatest_const1" };
+
+XFA_INIT(xfatest_t, xfatest_use);
+XFA_INIT_CONST(xfatest_t, xfatest_use_const);
+
+XFA(xfatest_use, 0) xfatest_t _xfatest_use1 = { .val = 3333, .text = "xfatest_use1" };
+XFA(xfatest_use, 0) xfatest_t _xfatest_use_again = { .val = 555, .text = "xfatest use again" };
+XFA_CONST(xfatest_use_const, 0) xfatest_t _xfatest_use_const1 = { .val = 4444, .text = "xfatest_use_const1" };
+
+int hack1;
+/** @} */
diff --git a/tests/unittests/tests-core/tests-core-xfa-data2.c b/tests/unittests/tests-core/tests-core-xfa-data2.c
new file mode 100644
index 000000000000..1084cdb82735
--- /dev/null
+++ b/tests/unittests/tests-core/tests-core-xfa-data2.c
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2018 Eistec AB
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @addtogroup  unittests
+ * @{
+ *
+ * @file
+ * @brief       Data elements for the core/xfa unit test
+ *
+ * @author      Joakim Nohlgård <joakim.nohlgard@eistec.se>
+ */
+#include "xfa.h"
+#include "tests-core-xfa.h"
+
+XFA(xfatest, 0) xfatest_t _xfatest2 = { .val = 0xbeef, .text = "another test string" };
+XFA_CONST(xfatest_const, 0) xfatest_t _xfatest_const2 = { .val = 32444, .text = "const string xfa 2" };
+XFA(xfatest_use, 0) xfatest_t _xfatest_use2 = { .val = 11111, .text = "xfatest_use2" };
+XFA_CONST(xfatest_use_const, 0) xfatest_t _xfatest_use_const2 = { .val = 22222, .text = "xfatest_use_const2" };
+
+int hack2;
+/** @} */
diff --git a/tests/unittests/tests-core/tests-core-xfa.c b/tests/unittests/tests-core/tests-core-xfa.c
new file mode 100644
index 000000000000..f21afd44627b
--- /dev/null
+++ b/tests/unittests/tests-core/tests-core-xfa.c
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2018 Eistec AB
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+#include <stdint.h>
+#include "xfa.h"
+
+#include "embUnit.h"
+
+#include "tests-core.h"
+#include "tests-core-xfa.h"
+
+extern int hack1;
+extern int hack2;
+
+XFA_INIT(xfatest_t, xfatest);
+XFA_INIT_CONST(xfatest_t, xfatest_const);
+XFA_USE(xfatest_t, xfatest_use);
+XFA_USE_CONST(xfatest_t, xfatest_use_const);
+
+/* Verifying that cross file array linking is correct by iterating over an external array */
+static void test_xfa_data(void)
+{
+    hack1 = hack2;
+
+    unsigned n = XFA_LEN(xfatest_t, xfatest);
+    TEST_ASSERT_EQUAL_INT(2, n);
+    unsigned found = 0;
+    for (unsigned k = 0; k < n; ++k) {
+        /* we do not want to enforce the order of the data elements */
+        switch (xfatest[k].val) {
+            case 12345:
+                /* tests-core-xfa-data1.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest1", xfatest[k].text);
+                ++found;
+                break;
+            case 0xbeef:
+                /* tests-core-xfa-data2.c */
+                TEST_ASSERT_EQUAL_STRING("another test string", xfatest[k].text);
+                ++found;
+                break;
+            default:
+                break;
+        }
+    }
+    TEST_ASSERT_EQUAL_INT(n, found);
+}
+
+static void test_xfa_const_data(void)
+{
+    unsigned n = XFA_LEN(xfatest_t, xfatest_const);
+    TEST_ASSERT_EQUAL_INT(2, n);
+    unsigned found = 0;
+    for (unsigned k = 0; k < n; ++k) {
+        /* we do not want to enforce the order of the data elements */
+        switch (xfatest_const[k].val) {
+            case 0xcafe:
+                /* tests-core-xfa-data1.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest_const1", xfatest_const[k].text);
+                ++found;
+                break;
+            case 32444:
+                /* tests-core-xfa-data2.c */
+                TEST_ASSERT_EQUAL_STRING("const string xfa 2", xfatest_const[k].text);
+                ++found;
+                break;
+            default:
+                break;
+        }
+    }
+    TEST_ASSERT_EQUAL_INT(n, found);
+}
+
+static void test_xfa_use_data(void)
+{
+    unsigned n = XFA_LEN(xfatest_t, xfatest_use);
+    TEST_ASSERT_EQUAL_INT(3, n);
+    unsigned found = 0;
+    for (unsigned k = 0; k < n; ++k) {
+        /* we do not want to enforce the order of the data elements */
+        switch (xfatest_use[k].val) {
+            case 3333:
+                /* tests-core-xfa-data1.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest_use1", xfatest_use[k].text);
+                ++found;
+                break;
+            case 555:
+                /* tests-core-xfa-data1.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest use again", xfatest_use[k].text);
+                ++found;
+                break;
+            case 11111:
+                /* tests-core-xfa-data2.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest_use2", xfatest_use[k].text);
+                ++found;
+                break;
+            default:
+                break;
+        }
+    }
+    TEST_ASSERT_EQUAL_INT(n, found);
+}
+
+static void test_xfa_use_const_data(void)
+{
+    unsigned n = XFA_LEN(xfatest_t, xfatest_use_const);
+    TEST_ASSERT_EQUAL_INT(2, n);
+    unsigned found = 0;
+    for (unsigned k = 0; k < n; ++k) {
+        /* we do not want to enforce the order of the data elements */
+        switch (xfatest_use_const[k].val) {
+            case 4444:
+                /* tests-core-xfa-data1.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest_use_const1", xfatest_use_const[k].text);
+                ++found;
+                break;
+            case 22222:
+                /* tests-core-xfa-data2.c */
+                TEST_ASSERT_EQUAL_STRING("xfatest_use_const2", xfatest_use_const[k].text);
+                ++found;
+                break;
+            default:
+                break;
+        }
+    }
+    TEST_ASSERT_EQUAL_INT(n, found);
+}
+
+Test *tests_core_xfa_tests(void)
+{
+    EMB_UNIT_TESTFIXTURES(fixtures) {
+        new_TestFixture(test_xfa_data),
+        new_TestFixture(test_xfa_const_data),
+        new_TestFixture(test_xfa_use_data),
+        new_TestFixture(test_xfa_use_const_data),
+    };
+
+    EMB_UNIT_TESTCALLER(core_xfa_tests, NULL, NULL,
+                        fixtures);
+
+    return (Test *)&core_xfa_tests;
+}
diff --git a/tests/unittests/tests-core/tests-core-xfa.h b/tests/unittests/tests-core/tests-core-xfa.h
new file mode 100644
index 000000000000..dc7b6b4c2354
--- /dev/null
+++ b/tests/unittests/tests-core/tests-core-xfa.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2018 Eistec AB
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @addtogroup  unittests
+ * @{
+ *
+ * @file
+ * @brief       Declarations for the core/xfa unit test
+ *
+ * @author      Joakim Nohlgård <joakim.nohlgard@eistec.se>
+ */
+#ifndef TESTS_CORE_XFA_H
+#define TESTS_CORE_XFA_H
+
+typedef struct {
+    unsigned val;
+    const char *text;
+} xfatest_t;
+
+#endif /* TESTS_CORE_XFA_H */
+
+/** @} */
diff --git a/tests/unittests/tests-core/tests-core.c b/tests/unittests/tests-core/tests-core.c
index 3551286e5d6e..fe7dfe2af539 100644
--- a/tests/unittests/tests-core/tests-core.c
+++ b/tests/unittests/tests-core/tests-core.c
@@ -19,4 +19,5 @@ void tests_core(void)
     TESTS_RUN(tests_core_priority_queue_tests());
     TESTS_RUN(tests_core_byteorder_tests());
     TESTS_RUN(tests_core_ringbuffer_tests());
+    TESTS_RUN(tests_core_xfa_tests());
 }
diff --git a/tests/unittests/tests-core/tests-core.h b/tests/unittests/tests-core/tests-core.h
index a22a58e4d8b1..294e888fe0d4 100644
--- a/tests/unittests/tests-core/tests-core.h
+++ b/tests/unittests/tests-core/tests-core.h
@@ -92,6 +92,13 @@ Test *tests_core_byteorder_tests(void);
  */
 Test *tests_core_ringbuffer_tests(void);
 
+/**
+ * @brief   Generates tests for xfa.h
+ *
+ * @return  embUnit tests if successful, NULL if not.
+ */
+Test *tests_core_xfa_tests(void);
+
 #ifdef __cplusplus
 }
 #endif

From 0bfa9e6717a9aa5255cec785e64a4677501fae2b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 22:31:53 +0200
Subject: [PATCH 23/27] tests/xfa: Add static check of XFA linking

---
 tests/xfa/Makefile | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/tests/xfa/Makefile b/tests/xfa/Makefile
index abe5a68a5500..0c1a5809ae48 100644
--- a/tests/xfa/Makefile
+++ b/tests/xfa/Makefile
@@ -3,3 +3,12 @@ APPLICATION = xfa
 include ../Makefile.tests_common
 
 include $(RIOTBASE)/Makefile.include
+
+all: static-test
+static-test: $(ELFFILE)
+	$(Q)TEST_STARTADDR=$$($(OBJDUMP) --syms $< | grep -E '\sxfatest_const$$' | awk '{ printf "0x%s", $$1}'); \
+	TEST_ENDADDR=$$($(OBJDUMP) --syms $< | grep -E '\sxfatest_const_end$$' | awk '{ printf "0x%s", $$1}'); \
+	if test ! $$((TEST_STARTADDR)) -lt $$((TEST_ENDADDR)); then \
+	  echo "Error: Static check of XFA linked const array failed, verify linker flags and try again" >&2; \
+	  exit 1; \
+	fi

From e209a3194c5132e18cc796ebfdf822f019ad8fe7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 22:32:09 +0200
Subject: [PATCH 24/27] squash xfa.h Fix XFA_USE macros

---
 core/include/xfa.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/core/include/xfa.h b/core/include/xfa.h
index 0ee9cd86d457..20ce349a5c9d 100644
--- a/core/include/xfa.h
+++ b/core/include/xfa.h
@@ -84,8 +84,8 @@
  * @param[in]   name    name of the cross-file array
  */
 #define XFA_USE_CONST(type, name) \
-    extern const type name [0]; \
-    extern const type name ## _end [0];
+    extern const type name []; \
+    extern const type name ## _end []
 
 /**
  * @brief Declare an external writable cross-file array
@@ -99,8 +99,8 @@
  * @param[in]   name    name of the cross-file array
  */
 #define XFA_USE(type, name) \
-    extern type name [0]; \
-    extern type name ## _end [0];
+    extern type name []; \
+    extern type name ## _end []
 
 /**
  * @brief Define variable in writable cross-file array

From 6d09bbd54d5153e44d9b46a058e63a28f4d70903 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 22:40:59 +0200
Subject: [PATCH 25/27] msp430: Add -Wno-pragmas for XFA in ancient GCC

---
 cpu/msp430_common/Makefile.include | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/cpu/msp430_common/Makefile.include b/cpu/msp430_common/Makefile.include
index ab6e0cf8c0d3..b34ce661583b 100644
--- a/cpu/msp430_common/Makefile.include
+++ b/cpu/msp430_common/Makefile.include
@@ -7,6 +7,9 @@ export CFLAGS += -DCPU_MODEL_$(MODEL)
 export UNDEF += $(BINDIR)/msp430_common/startup.o
 export USEMODULE += msp430_common msp430_common_periph periph_common
 
+# Ignore unknown pragmas (for xfa with gcc 4.6.3)
+CFLAGS += -Wno-pragmas
+
 DEFAULT_MODULE += oneway_malloc
 
 # include the msp430 common Makefile

From dbd06a987709c96e74dca25488b9fb5bac19a842 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joakim=20Nohlg=C3=A5rd?= <joakim.nohlgard@eistec.se>
Date: Mon, 14 May 2018 23:01:40 +0200
Subject: [PATCH 26/27] pic32_common: Add CPU specific xfa.ld variant

---
 cpu/mips_pic32_common/Makefile.include |  2 ++
 cpu/mips_pic32_common/ldscripts/xfa.ld | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+)
 create mode 100644 cpu/mips_pic32_common/ldscripts/xfa.ld

diff --git a/cpu/mips_pic32_common/Makefile.include b/cpu/mips_pic32_common/Makefile.include
index e0582db5dd7e..648adce56634 100644
--- a/cpu/mips_pic32_common/Makefile.include
+++ b/cpu/mips_pic32_common/Makefile.include
@@ -2,6 +2,8 @@ include $(RIOTCPU)/mips32r2_common/Makefile.include
 
 export INCLUDES += -I$(RIOTCPU)/mips_pic32_common/include
 
+LINKFLAGS += -L$(RIOTCPU)/mips_pic32_common/ldscripts
+
 USEMODULE += mips_pic32_common
 USEMODULE += mips_pic32_common_periph
 
diff --git a/cpu/mips_pic32_common/ldscripts/xfa.ld b/cpu/mips_pic32_common/ldscripts/xfa.ld
new file mode 100644
index 000000000000..ef5e17a9a41b
--- /dev/null
+++ b/cpu/mips_pic32_common/ldscripts/xfa.ld
@@ -0,0 +1,21 @@
+SECTIONS
+{
+    .data :
+    {
+        KEEP (*(SORT(.xfa.*)))
+    }
+    _fdata = ADDR(.data);
+    _edata = (_fdata + SIZEOF(.data));
+}
+
+INSERT BEFORE .sbss;
+
+SECTIONS
+{
+    .rodata :
+    {
+        KEEP (*(SORT(.roxfa.*)))
+    }
+}
+
+INSERT AFTER .dtors;

From 794b8aae7f2c8c4e9af71e89cc65671de3d3ba52 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ga=C3=ABtan=20Harter?= <gaetan.harter@fu-berlin.de>
Date: Mon, 4 Jun 2018 12:43:15 +0200
Subject: [PATCH 27/27] xfa: add a test script

Enable it for CI test
---
 tests/xfa/Makefile        |  4 ++++
 tests/xfa/tests/01-run.py | 26 ++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100755 tests/xfa/tests/01-run.py

diff --git a/tests/xfa/Makefile b/tests/xfa/Makefile
index 0c1a5809ae48..0252e6d773f1 100644
--- a/tests/xfa/Makefile
+++ b/tests/xfa/Makefile
@@ -2,6 +2,10 @@
 APPLICATION = xfa
 include ../Makefile.tests_common
 
+TEST_ON_CI_WHITELIST += all
+test:
+	tests/01-run.py
+
 include $(RIOTBASE)/Makefile.include
 
 all: static-test
diff --git a/tests/xfa/tests/01-run.py b/tests/xfa/tests/01-run.py
new file mode 100755
index 000000000000..e19b572a2c24
--- /dev/null
+++ b/tests/xfa/tests/01-run.py
@@ -0,0 +1,26 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2018 Gaëtan Harter <gaetan.harter@fu-berlin.de>
+#
+# This file is subject to the terms and conditions of the GNU Lesser
+# General Public License v2.1. See the file LICENSE in the top level
+# directory for more details.
+
+import os
+import sys
+
+
+def testfunc(child):
+    child.expect_exact('Cross file array test')
+    child.expect_exact('xfatest[2]:')
+    child.expect_exact('[0] = 1, "xfatest1"')
+    child.expect_exact('[1] = 2, "xfatest2"')
+    child.expect_exact('xfatest_const[2]:')
+    child.expect_exact('[0] = 123, "xfatest_const1"')
+    child.expect_exact('[1] = 45, "xfatest_const2"')
+
+
+if __name__ == "__main__":
+    sys.path.append(os.path.join(os.environ['RIOTTOOLS'], 'testrunner'))
+    from testrunner import run
+    exit(run(testfunc))