I think this one is obvious/trivial, but I'll ask anyway. OK?
Andrew. 2013-08-12 Andrew Haley <a...@redhat.com> Backport from mainline: * 2013-07-11 Andreas Schwab <sch...@suse.de> * config/aarch64/aarch64-linux.h (CPP_SPEC): Define. Index: gcc/config/aarch64/aarch64-linux.h =================================================================== --- gcc/config/aarch64/aarch64-linux.h (revision 201661) +++ gcc/config/aarch64/aarch64-linux.h (working copy) @@ -23,6 +23,8 @@ #define GLIBC_DYNAMIC_LINKER "/lib/ld-linux-aarch64.so.1" +#define CPP_SPEC "%{pthread:-D_REENTRANT}" + #define LINUX_TARGET_LINK_SPEC "%{h*} \ %{static:-Bstatic} \ %{shared:-shared} \