Make build CPU detection a tad more flexible

configure

@@ -71,8 +71,12 @@ if test -z "$source_path" -o "$source_path" = "." ; then
     source_path_used="no"
 fi
 
+classify_cpu ()
+{
+  cpu="$1"
+
   case "$cpu" in
-  i386|i486|i586|i686|i86pc|BePC|i686-AT386)
+    x86|i386|i486|i586|i686|i86pc|BePC|i686-AT386)
       cpu="x86"
     ;;
     x86_64|amd64)
@@ -108,9 +112,11 @@ case "$cpu" in
       cpu="s390"
     ;;
     *)
-    cpu="unknown"
+      echo "Unsupported CPU: $cpu"
+      exit 1
     ;;
   esac
+}
 
 for opt do
   eval opt=\"$opt\"
@@ -141,14 +147,6 @@ for opt do
   ;;
   --cross-prefix=*) cross_prefix=`echo $opt | cut -d '=' -f 2`
   ;;
-  --cc=*) cc=`echo $opt | cut -d '=' -f 2`
-  ;;
-  --extra-cflags=*) CFLAGS="${opt#--extra-cflags=}"
-  ;;
-  --extra-ldflags=*) LDFLAGS="${opt#--extra-ldflags=}"
-  ;;
-  --extra-libs=*) extralibs=${opt#--extra-libs=}
-  ;;
   --sysincludepaths=*) tcc_sysincludepaths=`echo $opt | cut -d '=' -f 2`
   ;;
   --libpaths=*) tcc_libpaths=`echo $opt | cut -d '=' -f 2`
@@ -157,7 +155,15 @@ for opt do
   ;;
   --elfinterp=*) tcc_elfinterp=`echo $opt | cut -d '=' -f 2`
   ;;
-  --cpu=*) cpu=`echo $opt | cut -d '=' -f 2`
+  --cc=*) cc=`echo $opt | cut -d '=' -f 2`
+  ;;
+  --extra-cflags=*) CFLAGS="${opt#--extra-cflags=}"
+  ;;
+  --extra-ldflags=*) LDFLAGS="${opt#--extra-ldflags=}"
+  ;;
+  --extra-libs=*) extralibs=${opt#--extra-libs=}
+  ;;
+  --cpu=*) build_cpu=`echo $opt | cut -d '=' -f 2`
   ;;
   --enable-gprof) gprof="yes"
   ;;
@@ -186,6 +192,8 @@ for opt do
   esac
 done
 
+classify_cpu "$cpu"
+
 # Checking for CFLAGS
 if test -z "$CFLAGS"; then
     CFLAGS="-Wall -g -O2"
@@ -271,6 +279,7 @@ Advanced options (experts only):
   --cc=CC                  use C compiler CC [$cc]
   --extra-cflags=          specify compiler flags [$CFLAGS]
   --extra-ldflags=         specify linker options []
+  --cpu=CPU                CPU [$cpu]
   --strip-binaries         strip symbol tables from resulting binaries
   --disable-static         make libtcc.so instead of libtcc.a
   --disable-rpath          disable use of -rpath with the above
@@ -356,8 +365,8 @@ Doc directory       $docdir
 Target root prefix  $sysroot
 Source path      $source_path
 C compiler       $cc
+Build CPU        $cpu
 Target OS        $targetos
-CPU              $cpu
 Big Endian       $bigendian
 gprof enabled    $gprof
 cross compilers  $build_cross