upcoming patch ip fragmentation example fails to with gcc 4.8.4 on linking __atomic_compare_exchange_16 functions on x86. For some version of gcc both -latomic and -mcx16 needs to be provided in that case. For clang only -mcx16. That options are set internally for platform but do not set for examples. This patch unhides setting this options, make them common and printed on configure log.
Signed-off-by: Maxim Uvarov <maxim.uva...@linaro.org> --- v2: unhide options and make frag code compile. CI now happy: https://travis-ci.org/muvarov/odp/builds/202380977 configure.ac | 16 ---------- platform/linux-generic/m4/configure.m4 | 57 ++++++++++++++++++++++++++++++++++ 2 files changed, 57 insertions(+), 16 deletions(-) diff --git a/configure.ac b/configure.ac index 6153efd2..a514f6be 100644 --- a/configure.ac +++ b/configure.ac @@ -314,22 +314,6 @@ ODP_CFLAGS="$ODP_CFLAGS -std=c99" # Extra flags for example to suppress certain warning types ODP_CFLAGS="$ODP_CFLAGS $ODP_CFLAGS_EXTRA" -######################################################################### -# Check if compiler supports cmpxchng16 -########################################################################## -if test "${CC}" != "gcc" -o ${CC_VERSION_MAJOR} -ge 5; then - my_save_cflags="$CFLAGS" - - CFLAGS=-mcx16 - AC_MSG_CHECKING([whether CC supports -mcx16]) - AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])], - [AC_MSG_RESULT([yes])] - [ODP_CFLAGS="$ODP_CFLAGS $CFLAGS"], - [AC_MSG_RESULT([no])] - ) - CFLAGS="$my_save_cflags" -fi - ########################################################################## # Default include setup ########################################################################## diff --git a/platform/linux-generic/m4/configure.m4 b/platform/linux-generic/m4/configure.m4 index d3e5528c..92172d4b 100644 --- a/platform/linux-generic/m4/configure.m4 +++ b/platform/linux-generic/m4/configure.m4 @@ -28,6 +28,63 @@ AC_LINK_IFELSE( echo "Use newer version. For gcc > 4.7.0" exit -1) +######################################################################### +# Check if compiler supports cmpxchng16 +########################################################################## +my_save_cflags="$CFLAGS" + +CFLAGS=-mcx16 +AC_MSG_CHECKING([whether CC supports -mcx16]) +AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])], + [AC_MSG_RESULT([yes])] + [MCX16_CFLAGS="-mcx16"], + [AC_MSG_RESULT([no])] + ) +CFLAGS="$my_save_cflags" + +######################################################################### +# Check if compiler supports __atomic_compare_exchange +########################################################################## +my_save_cflags="$CFLAGS" +LD_LIBATOMIC="" + +AC_MSG_CHECKING(if libatomic required) +AC_LINK_IFELSE( + [AC_LANG_SOURCE( + [[int main() { + unsigned __int128 x = 0, y = 0; + y = __atomic_load_n(&x, 0); + __atomic_store_n(&x, y, 0); + __atomic_compare_exchange_n(&x, &y, x, 0, 0, 0); + return 0; + } + ]])], + AC_MSG_RESULT(yes) + LD_LIBATOMIC="-latomic" + echo "adding -lbatomic", + AC_MSG_RESULT(no)) + +CFLAGS="$my_save_cflags $LD_LIBATOMIC $MCX16_CFLAGS" +AC_MSG_CHECKING([CFLAGS=$CFLAGS]) +AC_LINK_IFELSE( + [AC_LANG_SOURCE( + [[int main() { + unsigned __int128 x = 0, y = 0; + y = __atomic_load_n(&x, 0); + __atomic_store_n(&x, y, 0); + __atomic_compare_exchange_n(&x, &y, x, 0, 0, 0); + return 0; + } + ]])], + AC_MSG_RESULT(yes), + AC_MSG_RESULT(no) + echo "atomic operations compilation fail." + exit -1) + +# Restore LDFLAGS +CFLAGS="$my_save_cflags $MCX16_CFLAGS" +LDFLAGS="$LDFLAGS $LD_LIBATOMIC" + m4_include([platform/linux-generic/m4/odp_pthread.m4]) m4_include([platform/linux-generic/m4/odp_openssl.m4]) m4_include([platform/linux-generic/m4/odp_pcap.m4]) -- 2.11.0.295.gd7dffce
