test-release.sh: Add a way to specify --build to configure

[dsanders]

Summary

I currently have to specify --build=mips-linux-gnu or --build=mipsel-linux-gnu
in order to successfully recurse a 32-bit build of the compiler on my
mips64-linux-gnu and mips64el-linux-gnu targets. This is a bug and will be
fixed but in the meantime it will be useful to have a way to work around this.

[dsanders]

Closed by commit rL223369 (authored by @dsanders).

utils/release/test-release.sh

 do_dragonegg="no"
 do_fortran="no"
 do_objc="yes"
 do_64bit="yes"
 do_debug="no"
 do_asserts="no"
 do_compare="yes"
 BuildDir="`pwd`"
+BuildTriple=""
 
 function usage() {
     echo "usage: `basename $0` -release X.Y -rc NUM [OPTIONS]"
     echo ""
-    echo " -release X.Y      The release number to test."
-    echo " -rc NUM           The pre-release candidate number."
-    echo " -final            The final release candidate."
-    echo " -triple TRIPLE    The target triple for this machine."
-    echo " -j NUM            Number of compile jobs to run. [default: 3]"
-    echo " -build-dir DIR    Directory to perform testing in. [default: pwd]"
-    echo " -no-checkout      Don't checkout the sources from SVN."
-    echo " -no-64bit         Don't test the 64-bit version. [default: yes]"
-    echo " -enable-ada       Build Ada. [default: disable]"
-    echo " -disable-clang    Do not test clang. [default: enable]"
-    echo " -enable-dragonegg Test dragonegg. [default: disable]"
-    echo " -enable-fortran   Enable Fortran build. [default: disable]"
-    echo " -disable-objc     Disable ObjC build. [default: enable]"
-    echo " -test-debug       Test the debug build. [default: no]"
-    echo " -test-asserts     Test with asserts on. [default: no]"
-    echo " -no-compare-files Don't test that phase 2 and 3 files are identical."
-    echo " -use-gzip         Use gzip instead of xz."
+    echo " -release X.Y         The release number to test."
+    echo " -rc NUM              The pre-release candidate number."
+    echo " -final               The final release candidate."
+    echo " -triple TRIPLE       The target triple for this machine."
+    echo " -j NUM               Number of compile jobs to run. [default: 3]"
+    echo " -build-dir DIR       Directory to perform testing in. [default: pwd]"
+    echo " -no-checkout         Don't checkout the sources from SVN."
+    echo " -no-64bit            Don't test the 64-bit version. [default: yes]"
+    echo " -enable-ada          Build Ada. [default: disable]"
+    echo " -disable-clang       Do not test clang. [default: enable]"
+    echo " -enable-dragonegg    Test dragonegg. [default: disable]"
+    echo " -enable-fortran      Enable Fortran build. [default: disable]"
+    echo " -disable-objc        Disable ObjC build. [default: enable]"
+    echo " -test-debug          Test the debug build. [default: no]"
+    echo " -test-asserts        Test with asserts on. [default: no]"
+    echo " -no-compare-files    Don't test that phase 2 and 3 files are identical."
+    echo " -use-gzip            Use gzip instead of xz."
+    echo " -build-triple TRIPLE The build triple for this machine"
+    echo "                      [default: use config.guess]"
 }
 
 while [ $# -gt 0 ]; do
     case $1 in
         -release | --release )
             shift
             Release="$1"
             Release_no_dot="`echo $1 | sed -e 's,\.,,g'`"
             ;;
         -rc | --rc | -RC | --RC )
             shift
             RC="rc$1"
             ;;
         -final | --final )
             RC=final
             ;;
         -triple | --triple )
             shift
             Triple="$1"
             ;;
+        -build-triple | --build-triple )
+            shift
+            BuildTriple="$1"
+            ;;
         -j* )
             NumJobs="`echo $1 | sed -e 's,-j\([0-9]*\),\1,g'`"
             if [ -z "$NumJobs" ]; then
                 shift
                 NumJobs="$1"
             fi
             ;;
         -build-dir | --build-dir | -builddir | --builddir )
case $Flavor in
             echo ""
             return
             ;;
     esac
 
     echo "# Using C compiler: $c_compiler"
     echo "# Using C++ compiler: $cxx_compiler"
 
+    build_triple_option="${BuildTriple:+--build=$BuildTriple}"
+
     cd $ObjDir
     echo "# Configuring llvm $Release-$RC $Flavor"
     echo "# $BuildDir/llvm.src/configure --prefix=$InstallDir \
         --enable-optimized=$Optimized \
         --enable-assertions=$Assertions \
-        --disable-timestamps"
+        --disable-timestamps \
+        $build_triple_option"
     env CC="$c_compiler" CXX="$cxx_compiler" \
     $BuildDir/llvm.src/configure --prefix=$InstallDir \
         --enable-optimized=$Optimized \
         --enable-assertions=$Assertions \
         --disable-timestamps \
+        $build_triple_option \
         2>&1 | tee $LogDir/llvm.configure-Phase$Phase-$Flavor.log
     cd $BuildDir
 }
 
 function build_llvmCore() {
     Phase="$1"
     Flavor="$2"
     ObjDir="$3"