r264991 - Fix -Wdynamic-class-memaccess to skip invalid classes.

[Richard Trieu via cfe-commits]

Author: rtrieu
Date: Wed Mar 30 23:18:07 2016
New Revision: 264991

URL: http://llvm.org/viewvc/llvm-project?rev=264991&view=rev
Log:
Fix -Wdynamic-class-memaccess to skip invalid classes.

This warning sometimes will infinitely recurse on CXXRecordDecl's from
ill-formed recursive classes that have fields of themselves.  Skip processing
these classes to prevent this from happening.
Fixes https://llvm.org/bugs/show_bug.cgi?id=27142

Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp
    cfe/trunk/test/SemaCXX/warn-bad-memaccess.cpp

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=264991&r1=264990&r2=264991&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Wed Mar 30 23:18:07 2016
@@ -5611,7 +5611,7 @@ static const CXXRecordDecl *getContained
 
   const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
   RD = RD ? RD->getDefinition() : nullptr;
-  if (!RD)
+  if (!RD || RD->isInvalidDecl())
     return nullptr;
 
   if (RD->isDynamicClass())

Modified: cfe/trunk/test/SemaCXX/warn-bad-memaccess.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-bad-memaccess.cpp?rev=264991&r1=264990&r2=264991&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-bad-memaccess.cpp (original)
+++ cfe/trunk/test/SemaCXX/warn-bad-memaccess.cpp Wed Mar 30 23:18:07 2016
@@ -141,3 +141,16 @@ namespace N {
     N::memset(&x1, 0, sizeof x1);
   }
 }
+
+namespace recursive_class {
+struct S {
+  S v;
+  // expected-error at -1{{field has incomplete type 'recursive_class::S'}}
+  // expected-note at -3{{definition of 'recursive_class::S' is not complete until the closing '}'}}
+} a;
+
+int main() {
+  __builtin_memset(&a, 0, sizeof a);
+  return 0;
+}
+}