[PATCH] D116272: [Clang][Sema] Avoid crashing for va_arg expressions with bool argument

[Egor Zhdan via Phabricator via cfe-commits]

egorzhdan created this revision.
egorzhdan requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

This change fixes a compiler crash that was introduced in 
https://reviews.llvm.org/D103611: `Sema::BuildVAArgExpr` attempted to retrieve 
a corresponding signed type for `bool` by calling 
`ASTContext::getCorrespondingSignedType`.

rdar://86580370


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D116272

Files:
  clang/lib/Sema/SemaExpr.cpp
  clang/test/SemaCXX/varargs.cpp


Index: clang/test/SemaCXX/varargs.cpp
===================================================================
--- clang/test/SemaCXX/varargs.cpp
+++ clang/test/SemaCXX/varargs.cpp
@@ -53,6 +53,8 @@
 
   // Ensure that signed vs unsigned doesn't matter either.
   (void)__builtin_va_arg(ap, unsigned int);
+
+  (void)__builtin_va_arg(ap, bool); // expected-warning {{second argument to 
'va_arg' is of promotable type 'bool'; this va_arg has undefined behavior 
because arguments will be promoted to 'int'}}
 }
 
 #if __cplusplus >= 201103L
Index: clang/lib/Sema/SemaExpr.cpp
===================================================================
--- clang/lib/Sema/SemaExpr.cpp
+++ clang/lib/Sema/SemaExpr.cpp
@@ -15913,7 +15913,7 @@
       // promoted type and the underlying type are the same except for
       // signedness. Ask the AST for the correctly corresponding type and see
       // if that's compatible.
-      if (!PromoteType.isNull() &&
+      if (!PromoteType.isNull() && !UnderlyingType->isBooleanType() &&
           PromoteType->isUnsignedIntegerType() !=
               UnderlyingType->isUnsignedIntegerType()) {
         UnderlyingType =



Index: clang/test/SemaCXX/varargs.cpp
===================================================================
--- clang/test/SemaCXX/varargs.cpp
+++ clang/test/SemaCXX/varargs.cpp
@@ -53,6 +53,8 @@
 
   // Ensure that signed vs unsigned doesn't matter either.
   (void)__builtin_va_arg(ap, unsigned int);
+
+  (void)__builtin_va_arg(ap, bool); // expected-warning {{second argument to 'va_arg' is of promotable type 'bool'; this va_arg has undefined behavior because arguments will be promoted to 'int'}}
 }
 
 #if __cplusplus >= 201103L
Index: clang/lib/Sema/SemaExpr.cpp
===================================================================
--- clang/lib/Sema/SemaExpr.cpp
+++ clang/lib/Sema/SemaExpr.cpp
@@ -15913,7 +15913,7 @@
       // promoted type and the underlying type are the same except for
       // signedness. Ask the AST for the correctly corresponding type and see
       // if that's compatible.
-      if (!PromoteType.isNull() &&
+      if (!PromoteType.isNull() && !UnderlyingType->isBooleanType() &&
           PromoteType->isUnsignedIntegerType() !=
               UnderlyingType->isUnsignedIntegerType()) {
         UnderlyingType =

_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits