merge main into amd-staging (llvm#2309)

Author: z1_cciauto

clang/docs/ReleaseNotes.rst

@@ -273,6 +273,8 @@ C23 Feature Support
   be completed).
 - Fixed a failed assertion with an invalid parameter to the ``#embed``
   directive. Fixes #GH126940.
+- Fixed a crash when a declaration of a ``constexpr`` variable with an invalid
+  type. Fixes #GH140887
 
 C11 Feature Support
 ^^^^^^^^^^^^^^^^^^^

clang/lib/AST/ByteCode/Interp.cpp

@@ -670,7 +670,8 @@ bool CheckInitialized(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
   if (const auto *VD = Ptr.getDeclDesc()->asVarDecl();
       VD && (VD->isConstexpr() || VD->hasGlobalStorage())) {
 
-    if (!S.getLangOpts().CPlusPlus23 && VD == S.EvaluatingDecl) {
+    if (VD == S.EvaluatingDecl &&
+        !(S.getLangOpts().CPlusPlus23 && VD->getType()->isReferenceType())) {
       if (!S.getLangOpts().CPlusPlus14 &&
           !VD->getType().isConstant(S.getASTContext())) {
         // Diagnose as non-const read.

clang/lib/CodeGen/CGDecl.cpp

@@ -1944,6 +1944,7 @@ void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
 
   const VarDecl &D = *emission.Variable;
   auto DL = ApplyDebugLocation::CreateDefaultArtificial(*this, D.getLocation());
+  ApplyAtomGroup Grp(getDebugInfo());
   QualType type = D.getType();
 
   // If this local has an initializer, emit it now.

clang/lib/CodeGen/CGExpr.cpp

@@ -2222,6 +2222,8 @@ void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
   }
 
   llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
+  addInstToCurrentSourceAtom(Store, Value);
+
   if (isNontemporal) {
     llvm::MDNode *Node =
         llvm::MDNode::get(Store->getContext(),

clang/lib/Sema/SemaDecl.cpp

@@ -8681,7 +8681,8 @@ static bool CheckC23ConstexprVarType(Sema &SemaRef, SourceLocation VarLoc,
 
   if (CanonT->isRecordType()) {
     const RecordDecl *RD = CanonT->getAsRecordDecl();
-    if (llvm::any_of(RD->fields(), [&SemaRef, VarLoc](const FieldDecl *F) {
+    if (!RD->isInvalidDecl() &&
+        llvm::any_of(RD->fields(), [&SemaRef, VarLoc](const FieldDecl *F) {
           return CheckC23ConstexprVarType(SemaRef, VarLoc, F->getType());
         }))
       return true;

clang/lib/Sema/SemaInit.cpp

@@ -6618,7 +6618,7 @@ void InitializationSequence::InitializeFrom(Sema &S,
       // initializer present. However, we only do this for structure types, not
       // union types, because an unitialized field in a union is generally
       // reasonable, especially in C where unions can be used for type punning.
-      if (!Initializer && !Rec->isUnion()) {
+      if (!Initializer && !Rec->isUnion() && !Rec->isInvalidDecl()) {
         if (const FieldDecl *FD = getConstField(Rec)) {
           unsigned DiagID = diag::warn_default_init_const_field_unsafe;
           if (Var->getStorageDuration() == SD_Static ||

clang/test/AST/ByteCode/cxx23.cpp

@@ -73,6 +73,12 @@ constexpr int k(int n) {
 }
 constexpr int k0 = k(0);
 
+#if __cplusplus >= 202302L
+constexpr int &b = b; // all-error {{must be initialized by a constant expression}} \
+                      // all-note {{initializer of 'b' is not a constant expression}} \
+                      // all-note {{declared here}}
+#endif
+
 namespace StaticLambdas {
   constexpr auto static_capture_constexpr() {
     char n = 'n';

clang/test/DebugInfo/KeyInstructions/init-scalar.c

@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -gkey-instructions -x c++ %s -debug-info-kind=line-tables-only -emit-llvm -o - \
+// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank
+
+// RUN: %clang_cc1 -gkey-instructions -x c %s -debug-info-kind=line-tables-only -emit-llvm -o - \
+// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank
+
+void a() {
+// CHECK: store i32 0, ptr %A{{.*}}, !dbg [[G1R1:!.*]]
+    int A = 0;
+// CHECK: %add = add {{.*}}, !dbg [[G2R2:!.*]]
+// CHECK: store i32 %add, ptr %B, align 4, !dbg [[G2R1:!.*]]
+    int B = 2 * A + 1;
+}
+
+// CHECK: [[G1R1]] = !DILocation({{.*}}, atomGroup: 1, atomRank: 1)
+// CHECK: [[G2R2]] = !DILocation({{.*}}, atomGroup: 2, atomRank: 2)
+// CHECK: [[G2R1]] = !DILocation({{.*}}, atomGroup: 2, atomRank: 1)

clang/test/Sema/c2y-invalid-constexpr.c

@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c23 %s
+
+// This was previously causing a stack overflow when checking the valid
+// declaration of an invalid type. Ensure we issue reasonable diagnostics
+// instead of crashing.
+struct GH140887 { // expected-note {{definition of 'struct GH140887' is not complete until the closing '}'}}
+  GH140887();     // expected-error {{must use 'struct' tag to refer to type 'GH140887'}} \
+                     expected-error {{expected member name or ';' after declaration specifiers}} \
+                     expected-error {{field has incomplete type 'struct GH140887'}}
+};
+constexpr struct GH140887 a; // expected-error {{constexpr variable 'a' must be initialized by a constant expression}}
+

clang/test/Sema/warn-default-const-init-crash.c

@@ -0,0 +1,11 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+// This invalid code was causing a stack overflow, check that we issue
+// reasonable diagnostics and not crash.
+struct GH140887 {    // expected-note {{definition of 'struct GH140887' is not complete until the closing '}'}}
+  struct GH140887 s; // expected-error {{field has incomplete type 'struct GH140887'}}
+};
+
+void gh140887() {
+  struct GH140887 s;
+}