code review 152138: Build changes to support work on the BSDs.

src/make.bash

 #!/usr/bin/env bash
 # Copyright 2009 The Go Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
 
 set -e
 GOBIN="${GOBIN:-$HOME/bin}"
 export MAKEFLAGS=-j4
 
 if ! test -f $GOROOT/include/u.h
@@ skipping 11 matching lines @@
 
 case "$GOARCH" in
 amd64 | 386 | arm)
         ;;
 *)
         echo '$GOARCH is set to <'$GOARCH'>, must be amd64, 386, or arm' 1>&2
         exit 1
 esac
 
 case "$GOOS" in
-darwin | linux | nacl)
-        MAKE=make
-        ;;
-freebsd)
-        MAKE=gmake
+darwin | linux | nacl | freebsd)
         ;;
 *)
         echo '$GOOS is set to <'$GOOS'>, must be darwin, linux, or nacl' 1>&2
         exit 1
 esac
 
 rm -f $GOBIN/quietgcc
 CC=${CC:-gcc}
 sed -e "s|@CC@|$CC|" < quietgcc.bash > $GOBIN/quietgcc
 chmod +x $GOBIN/quietgcc
 
 rm -f $GOBIN/gomake
-MAKE=${MAKE:-make}
-sed -e "s|@MAKE@|$MAKE|" < gomake.bash > $GOBIN/gomake
+MAKE=make
+if ! make --version 2>/dev/null | grep 'GNU Make' >/dev/null; then
+        MAKE=gmake
+fi
+(echo '#!/bin/sh'; echo 'exec '$MAKE' "$@"') >$GOBIN/gomake
 chmod +x $GOBIN/gomake
 
 if ! (cd lib9 && which quietgcc) >/dev/null 2>&1; then
         echo "installed quietgcc as $GOBIN/quietgcc but 'which quietgcc' fails" 1>&2
         echo "double-check that $GOBIN is in your "'$PATH' 1>&2
         exit 1
 fi
 
 if [ -d /selinux -a -f /selinux/booleans/allow_execstack ] ; then
         if ! cat /selinux/booleans/allow_execstack | grep -c '^1 1$' >> /dev/null ; then
@@ skipping 36 matching lines @@
                 )  || exit 1
         esac
 done
 
 case "`uname`" in
 Darwin)
         echo;
         echo %%% run sudo.bash to install debuggers
         echo
 esac