From: Richard Trieu <rtrieu@google.com>
Date: Thu, 31 Mar 2016 04:18:07 +0000 (+0000)
Subject: Fix -Wdynamic-class-memaccess to skip invalid classes.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=bb39104647b6bc81ba627642f31c4487eeb59e8e;p=clang

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


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@264991 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 43195bd64f..ee39401d48 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -5611,7 +5611,7 @@ static const CXXRecordDecl *getContainedDynamicClass(QualType T,
 
   const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
   RD = RD ? RD->getDefinition() : nullptr;
-  if (!RD)
+  if (!RD || RD->isInvalidDecl())
     return nullptr;
 
   if (RD->isDynamicClass())
diff --git a/test/SemaCXX/warn-bad-memaccess.cpp b/test/SemaCXX/warn-bad-memaccess.cpp
index 67cde10bf4..55ce4a0da0 100644
--- a/test/SemaCXX/warn-bad-memaccess.cpp
+++ b/test/SemaCXX/warn-bad-memaccess.cpp
@@ -141,3 +141,16 @@ namespace N {
     N::memset(&x1, 0, sizeof x1);
   }
 }
+
+namespace recursive_class {
+struct S {
+  S v;
+  // expected-error@-1{{field has incomplete type 'recursive_class::S'}}
+  // expected-note@-3{{definition of 'recursive_class::S' is not complete until the closing '}'}}
+} a;
+
+int main() {
+  __builtin_memset(&a, 0, sizeof a);
+  return 0;
+}
+}