Some toolchains (such as sysmobts 201705 one) containing the TLS bug on
old ARM gcc versions (<7.3.0) also crash if the initial workaround found
is aplied (CFLAGS="-mtls-dialect=gnu2"). In that scenario, let's provide
a way to disable the workaround (to avoid "ld" crashing) and warn the
user about requirement to build with -O0 to avoid runtime crashes.
Related: OS#4062
Related: SYS#4628
Change-Id: I04ff8c702eabcf4f6e7b59e11aece2744267cefe
Check if compiler being used contains the bug. GCC 7.3.0 is the oldest
version containing the fix, and version 6.3.0 is known to contain the
bug. Bug is only known to appear so far only on ARM32. If the bug is
present, gcc will generate a wrong binary which wil lend up segfaulting
when accessing TLS (__thread) variables under certain conditions.
Related: OS#4062
Related: SYS#4628
Change-Id: I8acc2cf41b73da0c3290f1cefd79f2bc68b0e77d
The accelerated convolutional decoder uses SSSE3 instructions such
as PSIGNW (via _mm_sign_epi16) which go beyond what SSE3 offers. So
let's make sure we use the right compiler flag (-mssse3) and also the
right runtime check.
Without this patch, we would use illegal instructions e.g. on Opteron
Gen3 such as Opteron 2427, which are also used as build.opensuse.org
build hosts (build31 through build36) where we wouldn't pass "make
check" as a result.
Change-Id: I2754164384109f2821fd98ffb48f625893f2923d
Fixes: OS#2386
HAVE_AVX2, HAVE_SSE3 and HAVE_SSE4_1 were never defined if CPU
architecture doesn't match the (86*|x86_64*|amd64*) condition.
Change-Id: If0c3128f9768f95c1f5f955db242e71c81384c6c
This change adds a check whether compiler supports some SIMD
(Single Instruction, Multiple Data) instructions. It is enabled
by default, and can be disabled by configure option --disable-simd.
The check macro is based on the AX_EXT from autoconf-archive:
www.gnu.org/software/autoconf-archive/ax_ext.html
And depends on the ax_check_compile_flag macro:
www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
Currently only the following SIMD extensions are being checked:
AVX2, SSE3, SSE4.1, but adding others is also possible. All found
extensions are being defined in the 'config.h' header.
Change-Id: Idf8fff984bd936a75c7c307338df88ba4b005817
Even when removing AC_CONFIG_MACRO_DIR aclocal insisted that it
needs to have a m4 directory. Make it happy by providing one. As git
is not tracking directories I needed to add a dummy file.
Pau Espin
Harald Welte
Vadim Yanitskiy