-
The change fixes the following build failure on sparc T3 and older CPUs: ``` sparc-unknown-linux-gnu-gcc ... -O2 -mcpu=niagara2 ... -c rwlock.c {standard input}: Assembler messages: {standard input}:398: Error: Architecture mismatch on "pause ". {standard input}:398: (Requires v9e|v9v|v9m|m8; requested architecture is v9b.) make[1]: *** [Makefile:280: rwlock.o] Error 1 ``` `pause` insutruction exists only on `-mcpu=niagara4` (`T4`) and upper. The change adds `pause` configure-time autodetection and uses it if available. config.h.in got new `HAVE_SPARC_PAUSE` knob. Fallback is a fall-through no-op. Build-tested on: - sparc-unknown-linux-gnu-gcc (no `pause`, build succeeds) - sparc-unknown-linux-gnu-gcc -mcpu=niagara4 (`pause`, build succeeds) Reported-by: Rolf Eike Beer Bug: https://bugs.gentoo.org/691708 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
a5ad6b16