Sema: correct typo recovery with blocks

Handle blocks in the tree transform for the typo correction as otherwise, the
capture may miss.  This would trigger an assertion.  Thanks to Doug Gregor for
the help with this!

Fixes PR25001.

llvm-svn: 251729

clang/lib/Sema/SemaExprCXX.cpp

@@ -6545,6 +6545,8 @@ public:
 
   ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
 
+  ExprResult TransformBlockExpr(BlockExpr *E) { return Owned(E); }
+
   ExprResult Transform(Expr *E) {
     ExprResult Res;
     while (true) {

clang/test/SemaCXX/typo-correction-blocks.c

@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -triple i386-apple-macosx -fblocks -fsyntax-only -verify %s
+
+extern int h(int *);
+extern void g(int, void (^)(void));
+extern int fuzzys;                  // expected-note {{'fuzzys' declared here}}
+
+static void f(void *v) {
+  g(fuzzy, ^{                       // expected-error {{did you mean 'fuzzys'}}
+    int i = h(v);
+  });
+}
+