Re: [Qemu-devel] [PATCH v1 02/24] configure: add support for --cross-cc-FOO

["Alex Bennée" <alex.bennee@linaro.org>]

Philippe Mathieu-Daudé <f4bug@amsat.org> writes:

> On 04/10/2018 04:38 PM, Alex Bennée wrote:
>> This allows us to specify cross compilers for our guests. This is
>> useful for building test images/programs. Currently we re-run the
>> compile test for each target. I couldn't think of a way to cache the
>> value for a given arch without getting messier configure code.
>> 
>> The cross compiler for the guest is visible to each target as
>> CROSS_CC_GUEST in config-target.mak.
>> 
>> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
>> ---
>>  configure | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 50 insertions(+)
>> 
>> diff --git a/configure b/configure
>> index b402befe94..b5f3b3fe29 100755
>> --- a/configure
>> +++ b/configure
>> @@ -453,6 +453,13 @@ vxhs=""
>>  libxml2=""
>>  docker="no"
>>  
>> +# cross compilers defaults, can be overridden with --cross-cc-ARCH
>> +cross_cc_aarch64="aarch64-linux-gnu-gcc"
>> +cross_cc_arm="arm-linux-gnueabihf-gcc"
>> +cross_cc_powerpc="powerpc-linux-gnu-gcc"
>
> These seems distrib-specific... Should we add a case $distrib) ...?

I think of this more as sensible defaults - I would expect most people
using local cross-compilers to be manually setting them up with the
--cross-cc-FOO flag.

>
>> +
>> +enabled_cross_compilers=""
>> +
>>  supported_cpu="no"
>>  supported_os="no"
>>  bogus_os="no"
>> @@ -483,6 +490,11 @@ for opt do
>>    ;;
>>    --disable-debug-info) debug_info="no"
>>    ;;
>> +  --cross-cc-*[!a-zA-Z0-9_0]=*) error_exit "Passed bad --cross-cc-FOO option"
>> +  ;;
>> +  --cross-cc-*) cc_arch=${opt#--cross-cc-}
>> +                eval "cross_cc_${cc_arch}=\$optarg"
>> +  ;;
>>    esac
>>  done
>>  # OS specific
>> @@ -675,10 +687,12 @@ case "$cpu" in
>>    i386|i486|i586|i686|i86pc|BePC)
>>      cpu="i386"
>>      supported_cpu="yes"
>> +    cross_cc_i386=gcc
>>    ;;
>>    x86_64|amd64)
>>      cpu="x86_64"
>>      supported_cpu="yes"
>> +    cross_cc_x86_64=gcc
>>    ;;
>>    armv*b|armv*l|arm)
>>      cpu="arm"
>> @@ -912,6 +926,8 @@ for opt do
>>    ;;
>>    --disable-debug-info)
>>    ;;
>> +  --cross-cc-*)
>> +  ;;
>>    --enable-modules)
>>        modules="yes"
>>    ;;
>> @@ -6766,6 +6782,8 @@ case "$target" in
>>      ;;
>>  esac
>>  
>> +target_compiler=""
>> +
>>  mkdir -p $target_dir
>>  echo "# Automatically generated by configure - do not modify" > $config_target_mak
>>  
>> @@ -6794,6 +6812,7 @@ case "$target_name" in
>>      bflt="yes"
>>      mttcg="yes"
>>      gdb_xml_files="arm-core.xml arm-vfp.xml arm-vfp3.xml arm-neon.xml"
>> +    target_compiler=$cross_cc_arm
>>    ;;
>>    aarch64|aarch64_be)
>>      TARGET_ARCH=aarch64
>> @@ -6801,6 +6820,7 @@ case "$target_name" in
>>      bflt="yes"
>>      mttcg="yes"
>>      gdb_xml_files="aarch64-core.xml aarch64-fpu.xml arm-core.xml arm-vfp.xml arm-vfp3.xml arm-neon.xml"
>> +    target_compiler=$cross_cc_aarch64
>>    ;;
>>    cris)
>>    ;;
>> @@ -6842,6 +6862,7 @@ case "$target_name" in
>>    ;;
>>    ppc)
>>      gdb_xml_files="power-core.xml power-fpu.xml power-altivec.xml power-spe.xml"
>> +    target_compiler=$cross_cc_powerpc
>>    ;;
>>    ppcemb)
>>      TARGET_BASE_ARCH=ppc
>> @@ -6916,6 +6937,25 @@ if [ "$TARGET_BASE_ARCH" = "" ]; then
>>    TARGET_BASE_ARCH=$TARGET_ARCH
>>  fi
>>  
>> +# Do we have a cross compiler for this target?
>> +if has $target_compiler; then
>> +
>> +    cat > $TMPC << EOF
>> +#include <stdio.h>
>> +int main(void) {
>> +    printf("Hello World!\n");
>> +}
>> +EOF
>> +
>> +    if ! do_compiler $target_compiler -o $TMPE $TMPC -static ; then
>> +        target_compiler=""
>> +    else
>> +        enabled_cross_compilers="${enabled_cross_compilers} ${target_compiler}"
>> +    fi
>> +else
>> +    target_compiler=""
>> +fi
>> +
>>  symlink "$source_path/Makefile.target" "$target_dir/Makefile"
>>  
>>  upper() {
>> @@ -6989,6 +7029,10 @@ if test "$target_bsd_user" = "yes" ; then
>>    echo "CONFIG_BSD_USER=y" >> $config_target_mak
>>  fi
>>  
>> +if test -n "$target_compiler"; then
>> +  echo "CROSS_CC_GUEST=$target_compiler" >> $config_target_mak
>> +fi
>> +
>>  # generate QEMU_CFLAGS/LDFLAGS for targets
>>  
>>  cflags=""
>> @@ -7111,6 +7155,12 @@ echo "QEMU_CFLAGS+=$cflags" >> $config_target_mak
>>  
>>  done # for target in $targets
>>  
>> +if test -n "$enabled_cross_compilers"; then
>> +    echo
>> +    echo "NOTE: cross-compilers enabled:"
>> +    printf '%s\n' $enabled_cross_compilers | sort -u
>> +fi
>> +
>>  if [ "$dtc_internal" = "yes" ]; then
>>    echo "config-host.h: subdir-dtc" >> $config_host_mak
>>  fi
>> 


-- 
Alex Bennée