c4ffd48aba
This applies default compiler flags to .S files, in particular removing the "-pedantic" option, which is desirable because there is nothing to reasonably warn about; and the only thing that gcc warns about is that you allegedly can't correctly invoke GLUE2 in lib/builtins/assembly.h on platforms for which USER_LABEL_PREFIX is the empty string. In the gcc bug https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33305 that added the warning, a commenter notes that giving a macro of zero characters to another macro is not precisely the same as failing to supply an argument, and "there is a widespread belief in C++ community that such usage is valid". Unfortunately the only way to silence the warning is to avoid -pedantic. Differential Revision: http://reviews.llvm.org/D10713 llvm-svn: 243446