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         $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         get_version_line | sed 's/^.* version \([0-9][^ ]*\) .*/\1/'
  21 }
  22
  23 print_flags() {
  24         family=$1
  25         version=$(get_version | cut -f 1 -d .)
  26
  27         # Print a feature flag not only for the current version, but also
  28         # for any prior versions we encompass. This avoids needing to do
  29         # numeric comparisons in make, which are awkward.
  30         while test "$version" -gt 0
  31         do
  32                 echo $family$version
  33                 version=$((version - 1))
  34         done
  35 }
  36
  37 case "$(get_family)" in
  38 gcc)
  39         print_flags gcc
  40         ;;
  41 clang)
  42         print_flags clang
  43         ;;
  44 "FreeBSD clang")
  45         print_flags clang
  46         ;;
  47 "Apple LLVM")
  48         print_flags clang
  49         ;;
  50 *)
  51         : unknown compiler family
  52         ;;
  53 esac