Testcase: template <typename T> struct M; void foo() { (M<short> []) {{3}}; } Crashes with: clang: /home/eli/llvmgbuild/tools/clang/lib/AST/../../include/clang/AST/DeclCXX.h:382: const clang::CXXRecordDecl::DefinitionData& clang::CXXRecordDecl::data() const: Assertion `DefinitionData && "queried property of class with no definition"' failed.
Erm, the valid version of the testcase: template <typename T> struct M { T m; }; void foo() { (M<short> []) {{3}}; }
Fixed at r118428.