Per glibc feature_test_macros(7), setting compiler flags to -std=c11 (or any c* variant like c99) enforces strict ANSI mode. Enforcing strict ANSI makes all declarations under _GNU_SOURCE unavailable. This leads to build warnings in the form of: warning: implicit declaration of function â??syscallâ?? Thus replace -std=c11 with -std=gnu11 Signed-off-by: Ahmed S. Darwish <darwish.07 at gmail.com> --- configure.ac | 4 ++-- src/Makefile.am | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/configure.ac b/configure.ac index 8454e4c..fc1e299 100644 --- a/configure.ac +++ b/configure.ac @@ -176,9 +176,9 @@ esac #### Compiler flags #### -AX_CHECK_COMPILE_FLAG([-std=c11], +AX_CHECK_COMPILE_FLAG([-std=gnu11], [], - [AC_MSG_ERROR([*** Compiler does not support -std=c11])], + [AC_MSG_ERROR([*** Compiler does not support -std=gnu11])], [-pedantic -Werror]) AX_APPEND_COMPILE_FLAGS( diff --git a/src/Makefile.am b/src/Makefile.am index aa96999..b979d46 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -48,7 +48,7 @@ AM_CPPFLAGS = \ -DPA_SRCDIR=\"$(abs_srcdir)\" \ -DPA_BUILDDIR=\"$(abs_builddir)\" \ -DPULSE_LOCALEDIR=\"$(localedir)\" -AM_CFLAGS = -std=c11 \ +AM_CFLAGS = -std=gnu11 \ $(PTHREAD_CFLAGS) AM_CXXFLAGS = -std=c++11 \ $(PTHREAD_CFLAGS) Regards, -- Darwish http://darwish.chasingpointers.com