Document compatibility with earlier ProPolice implementation.

[thirdparty/gcc.git] / gcc / c-cppbuiltin.c

diff --git a/gcc/c-cppbuiltin.c b/gcc/c-cppbuiltin.c
index 44c7a3797ddb0305c559249e6ad72f4c3eb1cdd0..9020e0b49f9493c3e1a2bcdbd87fc73d352a1cf0 100644 (file)
--- a/gcc/c-cppbuiltin.c
+++ b/gcc/c-cppbuiltin.c
@@ -440,7 +440,9 @@ c_cpp_builtins (cpp_reader *pfile)
   if (targetm.handle_pragma_extern_prefix)
     cpp_define (pfile, "__PRAGMA_EXTERN_PREFIX");
 
-  /* Make the choice of the stack protector runtime visible to source code.  */
+  /* Make the choice of the stack protector runtime visible to source code.
+     The macro names and values here were chosen for compatibility with an
+     earlier implementation, i.e. ProPolice.  */
   if (flag_stack_protect == 2)
     cpp_define (pfile, "__SSP_ALL__=2");
   else if (flag_stack_protect == 1)