rust-lang · rust-bors · Apr 23, 2026 · Apr 21, 2026 · Apr 21, 2026
diff --git a/src/doc/rustc-dev-guide/src/tests/directives.md b/src/doc/rustc-dev-guide/src/tests/directives.md
@@ -326,6 +326,8 @@ See [Pretty-printer](compiletest.md#pretty-printer-tests).
 The following directives affect how certain command-line tools are invoked, in
 test suites that use those tools:
 
+- `skip-filecheck` avoids running LLVM's `FileCheck` tool in tests that would normally run it to check output.
+  - Used by codegen tests, assembly tests, and mir-opt tests.
 - `filecheck-flags` adds extra flags when running LLVM's `FileCheck` tool.
   - Used by [codegen tests](compiletest.md#codegen-tests),
   [assembly tests](compiletest.md#assembly-tests), and

diff --git a/src/tools/compiletest/src/directives.rs b/src/tools/compiletest/src/directives.rs
@@ -195,6 +195,9 @@ pub(crate) struct TestProps {
     /// Extra flags to pass to `llvm-cov` when producing coverage reports.
     /// Only used by the "coverage-run" test mode.
     pub(crate) llvm_cov_flags: Vec<String>,
+    /// Don't run LLVM's `filecheck` tool to check compiler output,
+    /// in tests that would normally run it.
+    pub(crate) skip_filecheck: bool,
     /// Extra flags to pass to LLVM's `filecheck` tool, in tests that use it.
     pub(crate) filecheck_flags: Vec<String>,
     /// Don't automatically insert any `--check-cfg` args
@@ -308,6 +311,7 @@ impl TestProps {
             mir_unit_test: None,
             remap_src_base: false,
             llvm_cov_flags: vec![],
+            skip_filecheck: false,
             filecheck_flags: vec![],
             no_auto_check_cfg: false,
             add_minicore: false,
@@ -438,7 +442,6 @@ impl TestProps {
         let check_no_run = |s| match (config.mode, s) {
             (TestMode::Ui, _) => (),
             (TestMode::Crashes, _) => (),
-            (TestMode::Codegen, "build-pass") => (),
             (mode, _) => panic!("`{s}` directive is not supported in `{mode}` tests"),
         };
         let pass_mode = if config.parse_name_directive(ln, "check-pass") {

diff --git a/src/tools/compiletest/src/directives/directive_names.rs b/src/tools/compiletest/src/directives/directive_names.rs
@@ -286,6 +286,7 @@ pub(crate) const KNOWN_DIRECTIVE_NAMES: &[&str] = &[
     "rustc-env",
     "rustfix-only-machine-applicable",
     "should-fail",
+    "skip-filecheck",
     "stderr-per-bitwidth",
     "test-mir-pass",
     "unique-doc-out-dir",

diff --git a/src/tools/compiletest/src/directives/handlers.rs b/src/tools/compiletest/src/directives/handlers.rs
@@ -1,7 +1,7 @@
 use std::collections::HashMap;
 use std::sync::{Arc, LazyLock};
 
-use crate::common::Config;
+use crate::common::{Config, TestMode};
 use crate::directives::{
     DirectiveLine, NormalizeKind, NormalizeRule, TestProps, parse_and_update_aux,
     parse_edition_range, split_flags,
@@ -312,6 +312,18 @@ fn make_directive_handlers_map() -> HashMap<&'static str, Handler> {
                 props.llvm_cov_flags.extend(split_flags(&flags));
             }
         }),
+        handler("skip-filecheck", |config, ln, props| {
+            let directive_name = ln.name;
+            // FIXME(Zalathar): Someday we should add unified support for declaring
+            // and checking which modes are supported by each directive.
+            if !matches!(config.mode, TestMode::Assembly | TestMode::Codegen | TestMode::MirOpt) {
+                panic!(
+                    "directive `//@ {directive_name}` is not supported by this test suite (mode: {mode:?})",
+                    mode = config.mode
+                );
+            }
+            config.set_name_directive(ln, directive_name, &mut props.skip_filecheck);
+        }),
         handler(FILECHECK_FLAGS, |config, ln, props| {
             if let Some(flags) = config.parse_name_value_directive(ln, FILECHECK_FLAGS) {
                 props.filecheck_flags.extend(split_flags(&flags));

diff --git a/src/tools/compiletest/src/runtest/assembly.rs b/src/tools/compiletest/src/runtest/assembly.rs
@@ -13,9 +13,11 @@ impl TestCx<'_> {
             self.fatal_proc_rec("compilation failed!", &proc_res);
         }
 
-        let proc_res = self.verify_with_filecheck(&output_path);
-        if !proc_res.status.success() {
-            self.fatal_proc_rec("verification with 'FileCheck' failed", &proc_res);
+        if !self.props.skip_filecheck {
+            let proc_res = self.verify_with_filecheck(&output_path);
+            if !proc_res.status.success() {
+                self.fatal_proc_rec("verification with 'FileCheck' failed", &proc_res);
+            }
         }
     }
 

diff --git a/src/tools/compiletest/src/runtest/codegen.rs b/src/tools/compiletest/src/runtest/codegen.rs
@@ -1,4 +1,4 @@
-use super::{PassMode, TestCx};
+use super::TestCx;
 
 impl TestCx<'_> {
     pub(super) fn run_codegen_test(&self) {
@@ -11,12 +11,11 @@ impl TestCx<'_> {
             self.fatal_proc_rec("compilation failed!", &proc_res);
         }
 
-        if let Some(PassMode::Build) = self.pass_mode() {
-            return;
-        }
-        let proc_res = self.verify_with_filecheck(&output_path);
-        if !proc_res.status.success() {
-            self.fatal_proc_rec("verification with 'FileCheck' failed", &proc_res);
+        if !self.props.skip_filecheck {
+            let proc_res = self.verify_with_filecheck(&output_path);
+            if !proc_res.status.success() {
+                self.fatal_proc_rec("verification with 'FileCheck' failed", &proc_res);
+            }
         }
     }
 }
diff --git a/src/tools/compiletest/src/runtest/mir_opt.rs b/src/tools/compiletest/src/runtest/mir_opt.rs
@@ -40,7 +40,7 @@ impl TestCx<'_> {
         let test_dir = self.testpaths.file.parent().unwrap();
         let test_crate = self.testpaths.file.file_stem().unwrap().replace('-', "_");
 
-        let MiroptTest { run_filecheck, suffix, files, passes: _ } = test_info;
+        let MiroptTest { suffix, files, passes: _ } = test_info;
 
         if self.config.bless {
             for e in glob(&format!("{}/{}.*{}.mir", test_dir, test_crate, suffix)).unwrap() {
@@ -89,7 +89,7 @@ impl TestCx<'_> {
             }
         }
 
-        if run_filecheck {
+        if !self.props.skip_filecheck {
             let output_path = self.output_base_name().with_extension("mir");
             let proc_res = self.verify_with_filecheck(&output_path);
             if !proc_res.status.success() {

diff --git a/src/tools/miropt-test-tools/src/lib.rs b/src/tools/miropt-test-tools/src/lib.rs
@@ -8,7 +8,6 @@ pub struct MiroptTestFile {
 }
 
 pub struct MiroptTest {
-    pub run_filecheck: bool,
     pub suffix: String,
     pub files: Vec<MiroptTestFile>,
     /// Vec of passes under test to be dumped
@@ -57,13 +56,15 @@ pub fn files_for_miropt_test(
     let test_crate = testfile.file_stem().unwrap().to_str().unwrap().replace('-', "_");
 
     let suffix = output_file_suffix(testfile, bit_width, panic_strategy);
-    let mut run_filecheck = true;
     let mut passes = Vec::new();
 
     for l in test_file_contents.lines() {
+        // FIXME(Zalathar): Remove this `skip-filecheck` migration error in 2027,
+        // or perhaps earlier if it seems no longer useful.
         if l.starts_with("// skip-filecheck") {
-            run_filecheck = false;
-            continue;
+            panic!(
+                "error: `// skip-filecheck` is no longer supported, use `//@ skip-filecheck` instead."
+            );
         }
         if l.starts_with("// EMIT_MIR ") {
             let test_name = l.trim_start_matches("// EMIT_MIR ").trim();
@@ -128,10 +129,7 @@ pub fn files_for_miropt_test(
 
             out.push(MiroptTestFile { expected_file, from_file, to_file });
         }
-        if !run_filecheck && l.trim_start().starts_with("// CHECK") {
-            panic!("error: test contains filecheck directive but is marked `skip-filecheck`");
-        }
     }
 
-    MiroptTest { run_filecheck, suffix, files: out, passes }
+    MiroptTest { suffix, files: out, passes }
 }
diff --git a/tests/codegen-llvm/scalable-vectors/tuple-intrinsics.rs b/tests/codegen-llvm/scalable-vectors/tuple-intrinsics.rs
@@ -1,4 +1,5 @@
-//@ build-pass
+// FIXME: The FileCheck directives in this test are unchecked and probably broken.
+//@ skip-filecheck
 //@ only-aarch64
 #![crate_type = "lib"]
 #![allow(incomplete_features, internal_features)]

diff --git a/tests/codegen-llvm/simd/simd-wide-sum.rs b/tests/codegen-llvm/simd/simd-wide-sum.rs
@@ -3,7 +3,7 @@
 //@ edition: 2021
 //@ only-x86_64
 //@ [mir-opt3]compile-flags: -Zmir-opt-level=3
-//@ [mir-opt3]build-pass
+//@ [mir-opt3] skip-filecheck
 
 // mir-opt3 is a regression test for https://github.com/rust-lang/rust/issues/98016
 

diff --git a/tests/mir-opt/README.md b/tests/mir-opt/README.md
@@ -57,7 +57,7 @@ The LLVM FileCheck tool is used to verify the contents of output MIR against `CH
 present in the test file. This works on the runtime MIR, generated by `--emit=mir`, and not
 on the output of a individual passes.
 
-Use `// skip-filecheck` to prevent FileCheck from running.
+Use `//@ skip-filecheck` to prevent FileCheck from running.
 
 To check MIR for function `foo`, start with a `// CHECK-LABEL fn foo(` directive.
 

diff --git a/tests/mir-opt/address_of.rs b/tests/mir-opt/address_of.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 // EMIT_MIR address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
 
 fn address_of_reborrow() {

diff --git a/tests/mir-opt/async_closure_fake_read_for_by_move.rs b/tests/mir-opt/async_closure_fake_read_for_by_move.rs
@@ -1,5 +1,5 @@
 //@ edition:2021
-// skip-filecheck
+//@ skip-filecheck
 
 enum Foo {
     Bar,

diff --git a/tests/mir-opt/async_closure_shims.rs b/tests/mir-opt/async_closure_shims.rs
@@ -1,5 +1,5 @@
 //@ edition:2021
-// skip-filecheck
+//@ skip-filecheck
 
 #![allow(unused)]
 

diff --git a/tests/mir-opt/async_drop_live_dead.rs b/tests/mir-opt/async_drop_live_dead.rs
@@ -1,5 +1,5 @@
 //@ edition:2024
-// skip-filecheck
+//@ skip-filecheck
 // EMIT_MIR_FOR_EACH_PANIC_STRATEGY
 
 #![feature(async_drop)]

diff --git a/tests/mir-opt/async_drop_mir_pin.rs b/tests/mir-opt/async_drop_mir_pin.rs
@@ -1,6 +1,6 @@
 //@edition: 2024
 //@ test-mir-pass: MentionedItems
-// skip-filecheck
+//@ skip-filecheck
 #![feature(async_drop)]
 #![allow(incomplete_features)]
 use std::future::AsyncDrop;

diff --git a/tests/mir-opt/box_conditional_drop_allocator.rs b/tests/mir-opt/box_conditional_drop_allocator.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 //@ test-mir-pass: ElaborateDrops
 //@ needs-unwind
 #![feature(allocator_api)]

diff --git a/tests/mir-opt/build_correct_coerce.rs b/tests/mir-opt/build_correct_coerce.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 
 // Validate that we record the target for the `as` coercion as `for<'a> fn(&'a (), &'a ())`,
 // and not `for<'a, 'b>(&'a (), &'b ())`. We previously did the latter due to a bug in

diff --git a/tests/mir-opt/building/async_await.rs b/tests/mir-opt/building/async_await.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 // This test makes sure that the coroutine MIR pass eliminates all calls to
 // `get_context`, and that the MIR argument type for an async fn and all locals
 // related to `yield` are `&mut Context`, and its return type is `Poll`.

diff --git a/tests/mir-opt/building/coroutine.rs b/tests/mir-opt/building/coroutine.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 //@ edition:2024
 //@ compile-flags: -Zmir-opt-level=0 -C panic=abort
 

diff --git a/tests/mir-opt/building/custom/aggregate_exprs.rs b/tests/mir-opt/building/custom/aggregate_exprs.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/arbitrary_let.rs b/tests/mir-opt/building/custom/arbitrary_let.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/arrays.rs b/tests/mir-opt/building/custom/arrays.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/as_cast.rs b/tests/mir-opt/building/custom/as_cast.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/assume.rs b/tests/mir-opt/building/custom/assume.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/composite_return.rs b/tests/mir-opt/building/custom/composite_return.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/consts.rs b/tests/mir-opt/building/custom/consts.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/enums.rs b/tests/mir-opt/building/custom/enums.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/operators.rs b/tests/mir-opt/building/custom/operators.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 //@ compile-flags: --crate-type=lib
 #![feature(custom_mir, core_intrinsics)]
 use std::intrinsics::mir::*;

diff --git a/tests/mir-opt/building/custom/projections.rs b/tests/mir-opt/building/custom/projections.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/references.rs b/tests/mir-opt/building/custom/references.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/simple_assign.rs b/tests/mir-opt/building/custom/simple_assign.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/custom/terminators.rs b/tests/mir-opt/building/custom/terminators.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![feature(custom_mir, core_intrinsics)]
 
 extern crate core;

diff --git a/tests/mir-opt/building/enum_cast.rs b/tests/mir-opt/building/enum_cast.rs
@@ -1,5 +1,5 @@
 //@ compile-flags: -Zmir-opt-level=0
-// skip-filecheck
+//@ skip-filecheck
 // EMIT_MIR enum_cast.foo.built.after.mir
 // EMIT_MIR enum_cast.bar.built.after.mir
 // EMIT_MIR enum_cast.boo.built.after.mir

diff --git a/tests/mir-opt/building/eq_never_type.rs b/tests/mir-opt/building/eq_never_type.rs
@@ -1,5 +1,5 @@
 //@ compile-flags: -Zmir-opt-level=0
-// skip-filecheck
+//@ skip-filecheck
 #![feature(never_type)]
 #![allow(unreachable_code)]
 

diff --git a/tests/mir-opt/building/issue_101867.rs b/tests/mir-opt/building/issue_101867.rs
@@ -1,5 +1,5 @@
 //@ compile-flags: -Zmir-opt-level=0
-// skip-filecheck
+//@ skip-filecheck
 // EMIT_MIR issue_101867.main.built.after.mir
 fn main() {
     let x: Option<u8> = Some(1);

diff --git a/tests/mir-opt/building/issue_110508.rs b/tests/mir-opt/building/issue_110508.rs
@@ -1,5 +1,5 @@
 //@ compile-flags: -Zmir-opt-level=0
-// skip-filecheck
+//@ skip-filecheck
 // EMIT_MIR issue_110508.{impl#0}-BAR.built.after.mir
 // EMIT_MIR issue_110508.{impl#0}-SELF_BAR.built.after.mir
 

diff --git a/tests/mir-opt/building/issue_49232.rs b/tests/mir-opt/building/issue_49232.rs
@@ -1,5 +1,5 @@
 //@ compile-flags: -Zmir-opt-level=0
-// skip-filecheck
+//@ skip-filecheck
 // We must mark a variable whose initialization fails due to an
 // abort statement as StorageDead.
 

diff --git a/tests/mir-opt/building/logical_or_in_conditional.rs b/tests/mir-opt/building/logical_or_in_conditional.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 //@ compile-flags: -Zmir-opt-level=0 -Z validate-mir
 //@ edition: 2024
 struct Droppy(u8);

diff --git a/tests/mir-opt/building/loop_match_diverges.rs b/tests/mir-opt/building/loop_match_diverges.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 #![allow(incomplete_features)]
 #![feature(loop_match)]
 #![crate_type = "lib"]

diff --git a/tests/mir-opt/building/match/deref-patterns/string.rs b/tests/mir-opt/building/match/deref-patterns/string.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 //@ compile-flags: -Z mir-opt-level=0 -C panic=abort
 
 #![feature(deref_patterns)]

diff --git a/tests/mir-opt/building/match/exponential_or.rs b/tests/mir-opt/building/match/exponential_or.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 // Test that simple or-patterns don't get expanded to exponentially large CFGs
 
 // EMIT_MIR exponential_or.match_tuple.SimplifyCfg-initial.after.mir

diff --git a/tests/mir-opt/building/match/match_false_edges.rs b/tests/mir-opt/building/match/match_false_edges.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 fn guard() -> bool {
     false
 }

diff --git a/tests/mir-opt/building/match/simple_match.rs b/tests/mir-opt/building/match/simple_match.rs
@@ -1,4 +1,4 @@
-// skip-filecheck
+//@ skip-filecheck
 // Test that we don't generate unnecessarily large MIR for very simple matches
 
 // EMIT_MIR simple_match.match_bool.built.after.mir