detect-compiler

   1 #!/bin/sh
   2 #
   3 # Probe the compiler for vintage, version, etc. This is used for setting
   4 # optional make knobs under the DEVELOPER knob.
   5
   6 CC="$*"
   7
   8 # we get something like (this is at least true for gcc and clang)
   9 #
  10 # FreeBSD clang version 3.4.1 (tags/RELEASE...)
  11 get_version_line() {
  12         LANG=C LC_ALL=C $CC -v 2>&1 | grep ' version '
  13 }
  14
  15 get_family() {
  16         get_version_line | sed 's/^\(.*\) version [0-9].*/\1/'
  17 }
  18
  19 get_version() {
  20         # A string that begins with a digit up to the next SP
  21         ver=$(get_version_line | sed 's/^.* version \([0-9][^ ]*\).*/\1/')
  22
  23         # There are known -variant suffixes that do not affect the
  24         # meaning of the main version number.  Strip them.
  25         ver=${ver%-win32}
  26         ver=${ver%-posix}
  27
  28         echo "$ver"
  29 }
  30
  31 print_flags() {
  32         family=$1
  33         version=$(get_version | cut -f 1 -d .)
  34
  35         # Print a feature flag not only for the current version, but also
  36         # for any prior versions we encompass. This avoids needing to do
  37         # numeric comparisons in make, which are awkward.
  38         while test "$version" -gt 0
  39         do
  40                 echo $family$version
  41                 version=$((version - 1))
  42         done
  43 }
  44
  45 case "$(get_family)" in
  46 gcc)
  47         print_flags gcc
  48         ;;
  49 clang | *" clang")
  50         print_flags clang
  51         ;;
  52 "Apple LLVM")
  53         print_flags clang
  54         ;;
  55 *)
  56         : unknown compiler family
  57         ;;
  58 esac