clang/test/Parser/backtrack-off-by-one.cpp

   1 // RUN: %clang_cc1 -verify %s
   2 // RUN: %clang_cc1 -verify %s -std=c++98
   3 // RUN: %clang_cc1 -verify %s -std=c++11
   4 // RUN: %clang_cc1 -verify %s -std=c++1z
   5
   6 // PR25946
   7 // We had an off-by-one error in an assertion when annotating A<int> below.  Our
   8 // error recovery checks if A<int> is a constructor declarator, and opens a
   9 // TentativeParsingAction. Then we attempt to annotate the token at the exact
  10 // position that we want to possibly backtrack to, and this used to crash.
  11
  12 template <typename T> class A {};
  13
  14 // expected-error@+1 {{expected '{' after base class list}}
  15 template <typename T> class B : T // not ',' or '{'
  16 #if __cplusplus < 201103L
  17 // expected-error@+8 {{expected ';' after top level declarator}}
  18 #endif
  19 #if __cplusplus <= 201402L
  20 // expected-error@+5 {{C++ requires a type specifier for all declarations}}
  21 #else
  22 // expected-error@+3 {{expected unqualified-id}}
  23 #endif
  24 // expected-error@+1 {{expected ';' after class}}
  25 A<int> {
  26 };