[llvm-branch-commits] [clang] 069b294 - Fix one of the regressions found in revert of concept sugaring

[Tobias Hieta via llvm-branch-commits]

Author: Erich Keane
Date: 2023-01-27T15:43:39+01:00
New Revision: 069b294d2ac1413060eb560778b9eaf486da8a0c

URL: https://github.com/llvm/llvm-project/commit/069b294d2ac1413060eb560778b9eaf486da8a0c
DIFF: https://github.com/llvm/llvm-project/commit/069b294d2ac1413060eb560778b9eaf486da8a0c.diff

LOG: Fix one of the regressions found in revert of concept sugaring

It seems that the sugaring patches had some pretty significant
interdependencies, and at least one issue exists that requires part of
the concept-sugaring patch.  I don't believe this to have anything to do
with the increased compile-times that were seen, so hopefully this will
fix our problems without further regressions.

See https://reviews.llvm.org/rG12cb1cb3720de8d164196010123ce1a8901d8122
for discussion.

Differential Revision: https://reviews.llvm.org/D142500

(cherry picked from commit 228462f755f0d459882b19115c60e8872a057b25)

Added: 
    clang/test/SemaTemplate/sugar-crashes.cpp

Modified: 
    clang/lib/Sema/SemaExprCXX.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index e3eef9323b2f8..abf5a72e7308a 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -1483,13 +1483,14 @@ Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
   //   Otherwise, if the type contains a placeholder type, it is replaced by the
   //   type determined by placeholder type deduction.
   DeducedType *Deduced = Ty->getContainedDeducedType();
-  if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
+  if (Deduced && !Deduced->isDeduced() &&
+      isa<DeducedTemplateSpecializationType>(Deduced)) {
     Ty = DeduceTemplateSpecializationFromInitializer(TInfo, Entity,
                                                      Kind, Exprs);
     if (Ty.isNull())
       return ExprError();
     Entity = InitializedEntity::InitializeTemporary(TInfo, Ty);
-  } else if (Deduced) {
+  } else if (Deduced && !Deduced->isDeduced()) {
     MultiExprArg Inits = Exprs;
     if (ListInitialization) {
       auto *ILE = cast<InitListExpr>(Exprs[0]);
@@ -2016,7 +2017,8 @@ ExprResult Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
 
   // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
   auto *Deduced = AllocType->getContainedDeducedType();
-  if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
+  if (Deduced && !Deduced->isDeduced() &&
+      isa<DeducedTemplateSpecializationType>(Deduced)) {
     if (ArraySize)
       return ExprError(
           Diag(*ArraySize ? (*ArraySize)->getExprLoc() : TypeRange.getBegin(),
@@ -2030,7 +2032,7 @@ ExprResult Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
         AllocTypeInfo, Entity, Kind, Exprs);
     if (AllocType.isNull())
       return ExprError();
-  } else if (Deduced) {
+  } else if (Deduced && !Deduced->isDeduced()) {
     MultiExprArg Inits = Exprs;
     bool Braced = (initStyle == CXXNewExpr::ListInit);
     if (Braced) {

diff  --git a/clang/test/SemaTemplate/sugar-crashes.cpp b/clang/test/SemaTemplate/sugar-crashes.cpp
new file mode 100644
index 0000000000000..fd0789d044e29
--- /dev/null
+++ b/clang/test/SemaTemplate/sugar-crashes.cpp
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -verify %s
+// expected-no-diagnostics
+
+
+struct StringPiece {
+  template <typename T,
+           typename = decltype(T())>
+             StringPiece(T str) {}
+};
+
+void f(StringPiece utf8) {}
+
+struct S {
+};
+
+void G() {
+  const auto s = S{};
+  StringPiece U{s};
+}
+