This was added in ~2004 for the sis driver, to detect whether it could use SSE for memcpy. Charmingly, the code to check whether that feature exists in the server is:
#if XORG_VERSION_CURRENT >= XORG_VERSION_NUMERIC(6,8,99,13,0) #define SISCHECKOSSSE /* Automatic check OS for SSE; requires SigIll facility */ #endif
Which means it has never worked in any modular server release.
A less gross way to do this is to check for SSE support with getauxval() or /proc/cpuinfo or similar. Since no driver is using the existing intercept mechanism, drop it.
722c8035d xfree86: Remove xf86InterceptSigIll
hw/xfree86/common/xf86.h | 1 -
hw/xfree86/common/xf86Events.c | 13 -------------
2 files changed, 14 deletions(-)