Fix for crash issues with comma operators with a void first operand, and 
some more bullet-proofing/enhancements for tryEvaluate.  This shouldn't 
cause any behavior changes except for handling cases where we were 
crashing before and being able to evaluate a few more cases in tryEvaluate.
 
This should settle the minor mess surrounding r59196.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@59224 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index c54fc40..c320cfc 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -733,6 +733,12 @@
 /// cast+dereference.
 bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx,
                                  SourceLocation *Loc, bool isEvaluated) const {
+  // Pretest for integral type; some parts of the code crash for types that
+  // can't be sized.
+  if (!getType()->isIntegralType()) {
+    if (Loc) *Loc = getLocStart();
+    return false;
+  }
   switch (getStmtClass()) {
   default:
     if (Loc) *Loc = getLocStart();