[PATCH v6 2/7] configure: cross-compiling with empty cross_prefix

[Joelle van Dyne <j@getutm.app>]

The iOS toolchain does not use the host prefix naming convention. So we
need to enable cross-compile options while allowing the PREFIX to be
blank.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Joelle van Dyne <j@getutm.app>
---
 configure | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/configure b/configure
index 7cd2ee0b9c..744d1990be 100755
--- a/configure
+++ b/configure
@@ -234,6 +234,7 @@ cpu=""
 iasl="iasl"
 interp_prefix="/usr/gnemul/qemu-%M"
 static="no"
+cross_compile="no"
 cross_prefix=""
 audio_drv_list=""
 block_drv_rw_whitelist=""
@@ -461,6 +462,7 @@ for opt do
   optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
   case "$opt" in
   --cross-prefix=*) cross_prefix="$optarg"
+                    cross_compile="yes"
   ;;
   --cc=*) CC="$optarg"
   ;;
@@ -1674,7 +1676,7 @@ $(echo Deprecated targets: $deprecated_targets_list | \
   --target-list-exclude=LIST exclude a set of targets from the default target-list
 
 Advanced options (experts only):
-  --cross-prefix=PREFIX    use PREFIX for compile tools [$cross_prefix]
+  --cross-prefix=PREFIX    use PREFIX for compile tools, PREFIX can be blank [$cross_prefix]
   --cc=CC                  use C compiler CC [$cc]
   --iasl=IASL              use ACPI compiler IASL [$iasl]
   --host-cc=CC             use C compiler CC [$host_cc] for code run at
@@ -6963,7 +6965,7 @@ if has $sdl2_config; then
 fi
 echo "strip = [$(meson_quote $strip)]" >> $cross
 echo "windres = [$(meson_quote $windres)]" >> $cross
-if test -n "$cross_prefix"; then
+if test "$cross_compile" = "yes"; then
     cross_arg="--cross-file config-meson.cross"
     echo "[host_machine]" >> $cross
     if test "$mingw32" = "yes" ; then
-- 
2.28.0