r337766 - [Sema] Fix crash on BlockExprs in a default member initializers

[Erik Pilkington via cfe-commits]

Author: epilk
Date: Mon Jul 23 15:47:37 2018
New Revision: 337766

URL: http://llvm.org/viewvc/llvm-project?rev=337766&view=rev
Log:
[Sema] Fix crash on BlockExprs in a default member initializers

Clang would crash when instantiating a BlockDecl that appeared in a
default-member-initializer of a class template. Fix this by deferring the
instantiation until we instantate the BlockExpr.

rdar://41200624

Differential revision: https://reviews.llvm.org/D49688

Modified:
    cfe/trunk/lib/Sema/SemaTemplateInstantiate.cpp
    cfe/trunk/test/SemaCXX/instantiate-blocks.cpp

Modified: cfe/trunk/lib/Sema/SemaTemplateInstantiate.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplateInstantiate.cpp?rev=337766&r1=337765&r2=337766&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplateInstantiate.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplateInstantiate.cpp Mon Jul 23 15:47:37 2018
@@ -2083,6 +2083,11 @@ Sema::InstantiateClass(SourceLocation Po
     if (Member->getDeclContext() != Pattern)
       continue;
 
+    // BlockDecls can appear in a default-member-initializer. They must be the
+    // child of a BlockExpr, so we only know how to instantiate them from there.
+    if (isa<BlockDecl>(Member))
+      continue;
+
     if (Member->isInvalidDecl()) {
       Instantiation->setInvalidDecl();
       continue;

Modified: cfe/trunk/test/SemaCXX/instantiate-blocks.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/instantiate-blocks.cpp?rev=337766&r1=337765&r2=337766&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/instantiate-blocks.cpp (original)
+++ cfe/trunk/test/SemaCXX/instantiate-blocks.cpp Mon Jul 23 15:47:37 2018
@@ -30,3 +30,12 @@ int main(void)
    noret((float)0.0, double(0.0)); // expected-note {{in instantiation of function template specialization 'noret<float, double>' requested here}}
 }
 
+namespace rdar41200624 {
+template <class T>
+struct S {
+  int (^p)() = ^{ return 0; };
+  T (^t)() = ^{ return T{}; };
+  T s = ^{ return T{}; }();
+};
+S<int> x;
+}