r253680 - [DebugInfo] Look through type sugar on union types when casting

[Reid Kleckner via cfe-commits]

Author: rnk
Date: Fri Nov 20 11:41:12 2015
New Revision: 253680

URL: http://llvm.org/viewvc/llvm-project?rev=253680&view=rev
Log:
[DebugInfo] Look through type sugar on union types when casting

Fixes PR25584.

Modified:
    cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
    cfe/trunk/test/CodeGenCXX/debug-info-anon-union-vars.cpp

Modified: cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDebugInfo.cpp?rev=253680&r1=253679&r2=253680&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDebugInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDebugInfo.cpp Fri Nov 20 11:41:12 2015
@@ -3329,7 +3329,7 @@ void CGDebugInfo::EmitGlobalVariable(llv
   // variable for each member of the anonymous union so that it's possible
   // to find the name of any field in the union.
   if (T->isUnionType() && DeclName.empty()) {
-    const RecordDecl *RD = cast<RecordType>(T)->getDecl();
+    const RecordDecl *RD = T->castAs<RecordType>()->getDecl();
     assert(RD->isAnonymousStructOrUnion() &&
            "unnamed non-anonymous struct or union?");
     GV = CollectAnonRecordDecls(RD, Unit, LineNo, LinkageName, Var, DContext);

Modified: cfe/trunk/test/CodeGenCXX/debug-info-anon-union-vars.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/debug-info-anon-union-vars.cpp?rev=253680&r1=253679&r2=253680&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/debug-info-anon-union-vars.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/debug-info-anon-union-vars.cpp Fri Nov 20 11:41:12 2015
@@ -29,11 +29,28 @@ void foo() {
   i = 8;
 }
 
+// A funky reinterpret cast idiom that we used to crash on.
+template <class T>
+unsigned char *buildBytes(const T v) {
+  static union {
+    unsigned char result[sizeof(T)];
+    T value;
+  };
+  value = v;
+  return result;
+}
+
+void instantiate(int x) {
+  buildBytes(x);
+}
+
 // CHECK: [[FILE:.*]] = !DIFile(filename: "{{.*}}debug-info-anon-union-vars.cpp",
 // CHECK: !DIGlobalVariable(name: "c",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
 // CHECK: !DIGlobalVariable(name: "d",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
 // CHECK: !DIGlobalVariable(name: "a",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
 // CHECK: !DIGlobalVariable(name: "b",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
+// CHECK: !DIGlobalVariable(name: "result", {{.*}} isLocal: false, isDefinition: true
+// CHECK: !DIGlobalVariable(name: "value", {{.*}} isLocal: false, isDefinition: true
 // CHECK: !DILocalVariable(name: "i", {{.*}}, flags: DIFlagArtificial
 // CHECK: !DILocalVariable(name: "c", {{.*}}, flags: DIFlagArtificial
 // CHECK: !DILocalVariable(