m4/ax_cc.m4

   1 dnl #
   2 dnl # check if were compiling with CLANG, autoconf GCC macro identifies CLANG as GCC
   3 dnl #
   4 AC_DEFUN([AX_CC_IS_CLANG],[
   5   AC_CACHE_CHECK([if compiler is clang], [ax_cv_cc_clang],[
   6
   7   AC_COMPILE_IFELSE(
   8     [AC_LANG_PROGRAM([], [[
   9     #ifndef __clang__
  10          not clang
  11     #endif
  12     ]])],
  13     [ax_cv_cc_clang=yes],
  14     [ax_cv_cc_clang=no])
  15   ])
  16 ])
  17
  18 AC_DEFUN([AX_CC_QUNUSED_ARGUMENTS_FLAG],[
  19   AC_CACHE_CHECK([for the compiler flag "-Qunused-arguments"], [ax_cv_cc_qunused_arguments_flag],[
  20
  21     CFLAGS_SAVED=$CFLAGS
  22     CFLAGS="$CFLAGS -Werror -Qunused-arguments -foobar"
  23
  24     AC_LANG_PUSH(C)
  25     AC_TRY_COMPILE(
  26       [],
  27       [return 0;],
  28       [ax_cv_cc_qunused_arguments_flag="yes"],
  29       [ax_cv_cc_qunused_arguments_flag="no"])
  30     AC_LANG_POP
  31
  32     CFLAGS="$CFLAGS_SAVED"
  33   ])
  34 ])
  35
  36 AC_DEFUN([AX_CC_WEVERYTHING_FLAG],[
  37   AC_CACHE_CHECK([for the compiler flag "-Weverything"], [ax_cv_cc_weverything_flag],[
  38
  39     CFLAGS_SAVED=$CFLAGS
  40     CFLAGS="$CFLAGS -Werror -Weverything -Wno-unused-macros -Wno-unreachable-code-return"
  41
  42     AC_LANG_PUSH(C)
  43     AC_TRY_COMPILE(
  44       [],
  45       [return 0;],
  46       [ax_cv_cc_weverything_flag="yes"],
  47       [ax_cv_cc_weverything_flag="no"])
  48     AC_LANG_POP
  49
  50     CFLAGS="$CFLAGS_SAVED"
  51   ])
  52 ])
  53
  54 AC_DEFUN([AX_CC_WDOCUMENTATION_FLAG],[
  55   AC_CACHE_CHECK([for the compiler flag "-Wdocumentation"], [ax_cv_cc_wdocumentation_flag],[
  56
  57     CFLAGS_SAVED=$CFLAGS
  58     CFLAGS="$CFLAGS -Werror -Wdocumentation"
  59
  60     AC_LANG_PUSH(C)
  61     AC_TRY_COMPILE(
  62       [],
  63       [return 0;],
  64       [ax_cv_cc_wdocumentation_flag="yes"],
  65       [ax_cv_cc_wdocumentation_flag="no"])
  66     AC_LANG_POP
  67
  68     CFLAGS="$CFLAGS_SAVED"
  69   ])
  70 ])
  71
  72 dnl #
  73 dnl # Determine the number of system cores we have
  74 dnl #
  75 AC_DEFUN([AX_SYSTEM_CORES],[
  76   AC_CACHE_CHECK([number of system cores], [ax_cv_system_cores],
  77     [
  78       AC_LANG_PUSH(C)
  79       AC_TRY_RUN(
  80         [
  81           #include <stdio.h>
  82           #include <stdint.h>
  83           #ifdef _WIN32
  84           #  include <windows.h>
  85           #elif MACOS
  86           #  include <sys/param.h>
  87           #  include <sys/sysctl.h>
  88           #else
  89           #  include <unistd.h>
  90           #endif
  91
  92           int main (int argc, char *argv[])
  93           {
  94             uint32_t count;
  95
  96             #ifdef WIN32
  97             SYSTEM_INFO sysinfo;
  98             GetSystemInfo(&sysinfo);
  99
 100             count = sysinfo.dwNumberOfProcessors;
 101
 102             #elif MACOS
 103             int nm[2];
 104             size_t len = 4;
 105
 106             nm[0] = CTL_HW;
 107             nm[1] = HW_AVAILCPU;
 108             sysctl(nm, 2, &count, &len, NULL, 0);
 109
 110             if(count < 1) {
 111               nm[1] = HW_NCPU;
 112               sysctl(nm, 2, &count, &len, NULL, 0);
 113               if(count < 1) {
 114                 count = 1;
 115               }
 116             }
 117
 118             #else
 119             count = sysconf(_SC_NPROCESSORS_ONLN);
 120             #endif
 121
 122             return count;
 123           }
 124         ],
 125         [ax_cv_system_cores=$?],
 126         [ax_cv_system_cores=$?],
 127         [ax_cv_system_cores=]
 128     )
 129     AC_LANG_POP
 130   ])
 131 ])
 132