Include debug info for types referenced only via explicit cast expressions.

Most of the debug info emission is powered essentially from function
definitions - if we emit the definition of a function, we emit the types
of its parameters, the members of those types, and so on and so forth.

For types that aren't referenced even indirectly due to this - because
they only appear in temporary expressions, not in any named variable, we
need to explicitly emit/add them as is done here. This is not the only
case of such code, and we might want to consider handling "void
func(void*); ... func(new T());" (currently debug info for T is not
emitted) at some point, though GCC doesn't. There's a much broader
solution to these issues, but it's a lot of work for possibly marginal
gain (but might help us improve the default -fno-standalone-debug
behavior to be even more aggressive in some places). See the original
review thread for more details.

Patch by jyoti allur (jyoti.yalamanchili@gmail.com)!

Differential Revision: http://reviews.llvm.org/D2498

llvm-svn: 218390

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 8d792262886..16373776015 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3347,3 +3347,11 @@ void CGDebugInfo::finalize() {
 
   DBuilder.finalize();
 }
+
+void CGDebugInfo::EmitExplicitCastType(QualType Ty) {
+  if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
+    return;
+  llvm::DIType DieTy = getOrCreateType(Ty, getOrCreateMainFile());
+  // Don't ignore in case of explicit cast where it is referenced indirectly.
+  DBuilder.retainType(DieTy);
+}