CGDebugInfo CreatedLimitedType: Drop file/line for RecordType with invalid location

For Clang synthesized `__va_list_tag` (`CreateX86_64ABIBuiltinVaListDecl`),
its DW_AT_decl_file/DW_AT_decl_line are arbitrarily set from `CurLoc`.

In a stage 2 `-DCMAKE_BUILD_TYPE=Debug` clang build, I observe that
in driver.cpp, DW_AT_decl_file/DW_AT_decl_line may be set to an `#include` line
(the transitively included file uses va_arg (`__builtin_va_arg`)).
This seems arbitrary. Drop that.

Reviewed By: #debug-info, dblaikie

Differential Revision: https://reviews.llvm.org/D94735

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 7ca230a..99944af 100644 (file)
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3332,10 +3332,14 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
   RecordDecl *RD = Ty->getDecl();
 
   // Get overall information about the record type for the debug info.
-  llvm::DIFile *DefUnit = getOrCreateFile(RD->getLocation());
-  const unsigned Line =
-      getLineNumber(RD->getLocation().isValid() ? RD->getLocation() : CurLoc);
   StringRef RDName = getClassName(RD);
+  const SourceLocation Loc = RD->getLocation();
+  llvm::DIFile *DefUnit = nullptr;
+  unsigned Line = 0;
+  if (Loc.isValid()) {
+    DefUnit = getOrCreateFile(Loc);
+    Line = getLineNumber(Loc);
+  }
 
   llvm::DIScope *RDContext = getDeclContextDescriptor(RD);
 

diff --git a/clang/test/CodeGen/X86/x86_64-arguments.c b/clang/test/CodeGen/X86/x86_64-arguments.c
index b51fe01..8898feb 100644 (file)
--- a/clang/test/CodeGen/X86/x86_64-arguments.c
+++ b/clang/test/CodeGen/X86/x86_64-arguments.c
@@ -1,8 +1,8 @@
-// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s | \
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -debug-info-kind=limited -o - %s | \
 // RUN:   FileCheck %s -check-prefix=CHECK -check-prefix=SSE -check-prefix=NO-AVX512
-// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -target-feature +avx | \
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -debug-info-kind=limited -o - %s -target-feature +avx | \
 // RUN:   FileCheck %s -check-prefix=CHECK -check-prefix=AVX -check-prefix=NO-AVX512
-// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -target-feature +avx512f | \
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -debug-info-kind=limited -o - %s -target-feature +avx512f | \
 // RUN:   FileCheck %s -check-prefix=CHECK -check-prefix=AVX -check-prefix=AVX512
 #include <stdarg.h>
 
@@ -545,3 +545,9 @@ struct t65 {
 // AVX: @f65(<8 x float> %{{[^,)]+}})
 void f65(struct t65 a0) {
 }
+
+/// The synthesized __va_list_tag does not have file/line fields.
+// CHECK:      = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "__va_list_tag",
+// CHECK-NOT:  file:
+// CHECK-NOT:  line:
+// CHECK-SAME: size: