[clang][modules] Strip LLVM options

[ributzka]

Currently, the dep scanner does not remove LLVM options from the argument list.
Since LLVM options shouldn't affect the AST, it is safe to remove them all.

[llvmbot]

@llvm/pr-subscribers-clang

Author: Juergen Ributzka (ributzka)

Changes

Currently, the dep scanner does not remove LLVM options from the argument list.
Since LLVM options shouldn't affect the AST, it is safe to remove them all.

---

Full diff: https://github.com/llvm/llvm-project/pull/75405.diff

2 Files Affected:

• (modified) clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp (+2)
• (added) clang/test/ClangScanDeps/strip-llvm-args.m (+49)

diff --git a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
index 4a3cd054f23d92..bfaa897851041d 100644
--- a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
+++ b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
@@ -119,6 +119,8 @@ makeCommonInvocationForModuleBuild(CompilerInvocation CI) {
   // units.
   CI.getFrontendOpts().Inputs.clear();
   CI.getFrontendOpts().OutputFile.clear();
+  // LLVM options are not going to affect the AST
+  CI.getFrontendOpts().LLVMArgs.clear();
 
   // TODO: Figure out better way to set options to their default value.
   CI.getCodeGenOpts().MainFileName.clear();
diff --git a/clang/test/ClangScanDeps/strip-llvm-args.m b/clang/test/ClangScanDeps/strip-llvm-args.m
new file mode 100644
index 00000000000000..a2ab1b4ab5c767
--- /dev/null
+++ b/clang/test/ClangScanDeps/strip-llvm-args.m
@@ -0,0 +1,49 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: sed -e "s|DIR|%/t|g" %t/cdb1.json.template > %t/cdb1.json
+
+// RUN: clang-scan-deps -compilation-database %t/cdb1.json -format experimental-full > %t/result1.txt
+// RUN: FileCheck %s -input-file %t/result1.txt
+
+// Verify that secondary actions get stripped, and that there's a single version
+// of module A.
+
+// CHECK:        "modules": [
+// CHECK-NEXT:     {
+// CHECK:            "command-line": [
+// CHECK-NOT:          "-treat-scalable-fixed-error-as-warning"
+// CHECK:            ]
+// CHECK:            "name": "A"
+// CHECK:          }
+// CHECK-NOT:        "name": "A"
+// CHECK:        "translation-units"
+
+//--- cdb1.json.template
+[
+  {
+    "directory": "DIR",
+    "command": "clang -Imodules/A -fmodules -fmodules-cache-path=DIR/module-cache -fimplicit-modules -fimplicit-module-maps -fsyntax-only DIR/t1.m",
+    "file": "DIR/t1.m"
+  },
+  {
+    "directory": "DIR",
+    "command": "clang -Imodules/A -fmodules -fmodules-cache-path=DIR/module-cache -fimplicit-modules -fimplicit-module-maps -mllvm -stackmap-version=2 -fsyntax-only DIR/t2.m",
+    "file": "DIR/t2.m"
+  }
+]
+
+//--- modules/A/module.modulemap
+
+module A {
+  umbrella header "A.h"
+}
+
+//--- modules/A/A.h
+
+typedef int A_t;
+
+//--- t1.m
+@import A;
+
+//--- t2.m
+@import A;

[jansvoboda11]

LGTM

[ributzka]

Thanks for the reviews.