[clang] d870a57 - [SemaCXX] Set promotion type for enum if its type is promotable to integer type even if it has no definition.

[Zequan Wu via cfe-commits]

Author: Zequan Wu
Date: 2022-07-21T11:23:21-07:00
New Revision: d870a575631d2cedab2ff237af8edd17916edc64

URL: https://github.com/llvm/llvm-project/commit/d870a575631d2cedab2ff237af8edd17916edc64
DIFF: https://github.com/llvm/llvm-project/commit/d870a575631d2cedab2ff237af8edd17916edc64.diff

LOG: [SemaCXX] Set promotion type for enum if its type is promotable to integer type even if it has no definition.

EnumDecl's promotion type is set either to the parsed type or calculated type
after completing its definition. When it's bool type and has no definition,
its promotion type is bool which is not allowed by clang.

Fixes #56560.

Differential Revision: https://reviews.llvm.org/D130210

Added: 
    

Modified: 
    clang/docs/ReleaseNotes.rst
    clang/lib/Sema/SemaDecl.cpp
    clang/test/CXX/conv/conv.prom/p4.cpp

Removed: 
    


################################################################################
diff  --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index cb64cd21fe853..d65fcdbeaa62d 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -192,6 +192,8 @@ Bug Fixes
   Fixes `Issue 56310 <https://github.com/llvm/llvm-project/issues/56310>`_.
 - Clang will now look through type sugar when checking a member function is a
   move assignment operator. Fixes `Issue 56456 <https://github.com/llvm/llvm-project/issues/56456>`_.
+- Fixed a crash when a variable with a bool enum type that has no definition
+  used in comparison operators. Fixes `Issue 56560 <https://github.com/llvm/llvm-project/issues/56560>`_.
 
 Improvements to Clang's diagnostics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

diff  --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 736c299f38bb8..8d2fc5331a0df 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -16209,7 +16209,10 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
           ED->setIntegerTypeSourceInfo(TI);
         else
           ED->setIntegerType(QualType(EnumUnderlying.get<const Type *>(), 0));
-        ED->setPromotionType(ED->getIntegerType());
+        QualType EnumTy = ED->getIntegerType();
+        ED->setPromotionType(EnumTy->isPromotableIntegerType()
+                                 ? Context.getPromotedIntegerType(EnumTy)
+                                 : EnumTy);
       }
     } else { // struct/union
       New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
@@ -16831,8 +16834,11 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
       if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
         ED->setIntegerTypeSourceInfo(TI);
       else
-        ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
-      ED->setPromotionType(ED->getIntegerType());
+        ED->setIntegerType(QualType(EnumUnderlying.get<const Type *>(), 0));
+      QualType EnumTy = ED->getIntegerType();
+      ED->setPromotionType(EnumTy->isPromotableIntegerType()
+                               ? Context.getPromotedIntegerType(EnumTy)
+                               : EnumTy);
       assert(ED->isComplete() && "enum with type should be complete");
     }
   } else {

diff  --git a/clang/test/CXX/conv/conv.prom/p4.cpp b/clang/test/CXX/conv/conv.prom/p4.cpp
index 8c86d2a1838da..be422f362d6e3 100644
--- a/clang/test/CXX/conv/conv.prom/p4.cpp
+++ b/clang/test/CXX/conv/conv.prom/p4.cpp
@@ -26,3 +26,10 @@ enum B2 : bool {
   // FIXME: DR1407 will make this ill-formed
   e = +false_ // desired-error {{conversion from 'int' to 'bool'}}
 };
+
+namespace GH56560 {
+enum GH56560_1 : bool;
+bool GH56560_2(GH56560_1 a, GH56560_1 b) {
+    return a == b;
+}
+} // namespace GH56560