From 4b919a21ce70e4ec6a920bd88c1febe26250fc27 Mon Sep 17 00:00:00 2001
From: Maor Hamami <hamamimaor@microsoft.com>
Date: Tue, 10 Mar 2026 14:14:32 +0200
Subject: [PATCH] support msvc

---
 CMakeLists.txt                | 15 +++++++
 src/fiber.c                   |  2 +-
 src/fiber_asm_amd64_win64.asm | 76 +++++++++++++++++------------------
 3 files changed, 54 insertions(+), 39 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 776bb58..fa4e0c9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -148,6 +148,21 @@ if(FIBER_OBJECT)
   set_target_properties(fiber PROPERTIES POSITION_INDEPENDENT_CODE ON)
 endif()
 
+# Set C standard on the target so it applies in both standalone and subdirectory
+# mode. The standalone code path above sets CMAKE_C_STANDARD, but that does not
+# propagate when fiber is consumed as a subdirectory.
+set_property(TARGET fiber PROPERTY C_STANDARD 99)
+set_property(TARGET fiber PROPERTY C_STANDARD_REQUIRED ON)
+set_property(TARGET fiber PROPERTY C_EXTENSIONS OFF)
+
+if(CMU_COMP_MSVC AND NOT CMU_COMP_GNUC)
+  # Pure MSVC (not clang-cl) needs /std:c11 to define __STDC_VERSION__, and
+  # never defines __STDC__ without /Za. Both are required by cxx-header-utils
+  # (hu/lang.h) for C language detection.
+  set_property(TARGET fiber PROPERTY C_STANDARD 11)
+  target_compile_definitions(fiber PRIVATE __STDC__=1)
+endif()
+
 if(FIBER_STANDALONE_PROJECT)
   enable_testing()
   add_subdirectory(test)
diff --git a/src/fiber.c b/src/fiber.c
index a3d7b4e..af34652 100644
--- a/src/fiber.c
+++ b/src/fiber.c
@@ -13,7 +13,7 @@
 #    include <unistd.h>
 #    if HU_C_11_P
 #        define ALIGNED_ALLOC aligned_alloc
-#    elif HU_OS_BSD_P || defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L
+#    elif HU_OS_BSD_P || HU_OS_APPLE_P || defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L
 #        define USE_POSIX_MEMALIGN 1
 #    else
 #        include <malloc.h>
diff --git a/src/fiber_asm_amd64_win64.asm b/src/fiber_asm_amd64_win64.asm
index 76927d7..031bbdb 100644
--- a/src/fiber_asm_amd64_win64.asm
+++ b/src/fiber_asm_amd64_win64.asm
@@ -8,50 +8,50 @@ fiber_asm_switch PROC
 
   mov [rcx], rsp
   mov rsp, [rdx]
-  mov [rcx+0x8], rax
-  mov rax, [rdx+0x8]
-  mov [rcx+0x10], rbx
-  mov rbx, [rdx+0x10]
-  mov [rcx+0x18], rbp
-  mov rbp, [rdx+0x18]
-  mov [rcx+0x20], rdi
-  mov rdi, [rdx+0x20]
-  mov [rcx+0x28], rsi
-  mov rsi, [rdx+0x28]
-  mov [rcx+0x30], r12
-  mov r12, [rdx+0x30]
-  mov [rcx+0x38], r13
-  mov r13, [rdx+0x38]
-  mov [rcx+0x40], r14
-  mov r14, [rdx+0x40]
-  mov [rcx+0x48], r15
-  mov r15, [rdx+0x48]
+  mov [rcx+8h], rax
+  mov rax, [rdx+8h]
+  mov [rcx+10h], rbx
+  mov rbx, [rdx+10h]
+  mov [rcx+18h], rbp
+  mov rbp, [rdx+18h]
+  mov [rcx+20h], rdi
+  mov rdi, [rdx+20h]
+  mov [rcx+28h], rsi
+  mov rsi, [rdx+28h]
+  mov [rcx+30h], r12
+  mov r12, [rdx+30h]
+  mov [rcx+38h], r13
+  mov r13, [rdx+38h]
+  mov [rcx+40h], r14
+  mov r14, [rdx+40h]
+  mov [rcx+48h], r15
+  mov r15, [rdx+48h]
 
-  lea rcx, [rcx+0x58]
+  lea rcx, [rcx+58h]
   and rcx, -16
-  lea rdx, [rdx+0x58]
+  lea rdx, [rdx+58h]
   and rdx, -16
 
   movaps [rcx], xmm6
   movaps xmm6, [rdx]
-  movaps [rcx+0x10], xmm7
-  movaps xmm7, [rdx+0x10]
-  movaps [rcx+0x20], xmm8
-  movaps xmm8, [rdx+0x20]
-  movaps [rcx+0x30], xmm9
-  movaps xmm9, [rdx+0x30]
-  movaps [rcx+0x40], xmm10
-  movaps xmm10, [rdx+0x40]
-  movaps [rcx+0x50], xmm11
-  movaps xmm11, [rdx+0x50]
-  movaps [rcx+0x60], xmm12
-  movaps xmm12, [rdx+0x60]
-  movaps [rcx+0x70], xmm13
-  movaps xmm13, [rdx+0x70]
-  movaps [rcx+0x80], xmm14
-  movaps xmm14, [rdx+0x80]
-  movaps [rcx+0x90], xmm15
-  movaps xmm15, [rdx+0x90]
+  movaps [rcx+10h], xmm7
+  movaps xmm7, [rdx+10h]
+  movaps [rcx+20h], xmm8
+  movaps xmm8, [rdx+20h]
+  movaps [rcx+30h], xmm9
+  movaps xmm9, [rdx+30h]
+  movaps [rcx+40h], xmm10
+  movaps xmm10, [rdx+40h]
+  movaps [rcx+50h], xmm11
+  movaps xmm11, [rdx+50h]
+  movaps [rcx+60h], xmm12
+  movaps xmm12, [rdx+60h]
+  movaps [rcx+70h], xmm13
+  movaps xmm13, [rdx+70h]
+  movaps [rcx+80h], xmm14
+  movaps xmm14, [rdx+80h]
+  movaps [rcx+90h], xmm15
+  movaps xmm15, [rdx+90h]
 
   jmp    rax
 fiber_asm_switch ENDP