mirror of
https://github.com/cuberite/polarssl.git
synced 2025-09-08 06:40:16 -04:00
9d9d45c6b2
Fixes #1910 With ebx added to the MULADDC_STOP clobber list to fix #1550, the inline assembly fails to build with GCC < 5 in PIC mode with the following error: include/mbedtls/bn_mul.h:46:13: error: PIC register clobbered by ‘ebx’ in ‘asm’ This is because older GCC versions treated the x86 ebx register (which is used for the GOT) as a fixed reserved register when building as PIC. This is fixed by an improved register allocator in GCC 5+. From the release notes: Register allocation improvements: Reuse of the PIC hard register, instead of using a fixed register, was implemented on x86/x86-64 targets. This improves generated PIC code performance as more hard registers can be used. https://www.gnu.org/software/gcc/gcc-5/changes.html As a workaround, detect this situation and disable the inline assembly, similar to the MULADDC_CANNOT_USE_R7 logic. Signed-off-by: Peter Korsgaard <peter@korsgaard.com>