Re: [PATCH] travis-ci: Use clang-10 for the [s390x] Clang (disable-tcg) job

[Thomas Huth <thuth@redhat.com>]

On 12/05/2021 17.26, Philippe Mathieu-Daudé wrote:
> On 5/12/21 5:22 PM, Philippe Mathieu-Daudé wrote:
>> On Ubuntu Bionic 18.04 LTS clang binary points to the 6.0 version:
>>
>>    $ clang --version
>>    clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final)
>>
>> However we can install clang-10 from the bionic-updates stream [*]
>> and use it, to silent the following warnings:
>>
>>       CC      pc-bios/s390-ccw/main.o
>>    clang: warning: optimization flag '-fno-delete-null-pointer-checks' is not supported [-Wignored-optimization-argument]
>>    clang: warning: argument unused during compilation: '-msoft-float' [-Wunused-command-line-argument]
>>    /home/travis/build/qemu/qemu/pc-bios/s390-ccw/main.c:284:5: warning: no previous prototype for function 'main' [-Wmissing-prototypes]
>>    int main(void)
>>        ^
>>    1 warning generated.
>>    clang: warning: optimization flag '-fno-delete-null-pointer-checks' is not supported [-Wignored-optimization-argument]
>>
>> [*] https://packages.ubuntu.com/bionic-updates/clang-10
>>
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>> ---
>> However this doesn't resolve:
>>
>>      /home/travis/build/philmd/qemu/pc-bios/s390-ccw/jump2ipl.c:67:18: error: invalid operand for instruction
>>          asm volatile("lghi 1,1\n\t"
>>                       ^
>>      <inline asm>:1:7: note: instantiated into assembly here
>>              lghi 1,1
>>                   ^
>>      /home/travis/build/philmd/qemu/pc-bios/s390-ccw/jump2ipl.c:67:29: error: invalid operand for instruction
>>          asm volatile("lghi 1,1\n\t"
>>                                  ^
>>      <inline asm>:2:7: note: instantiated into assembly here
>>              diag 1,1,0x308
>>                   ^
>>      2 errors generated.
>>      Makefile:20: recipe for target 'jump2ipl.o' failed
>>      make[1]: *** [jump2ipl.o] Error 1
>>
>> (see https://travis-ci.org/github/philmd/qemu/jobs/770920106#L1803,
>> https://travis-ci.org/github/philmd/qemu/jobs/770920522#L1818 for
>> more errors).
>> ---
>>   .travis.yml | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/.travis.yml b/.travis.yml
>> index 4609240b5aa..9c0deea9a06 100644
>> --- a/.travis.yml
>> +++ b/.travis.yml
>> @@ -278,6 +278,7 @@ jobs:
>>         compiler: clang
>>         addons:
>>           apt_packages:
>> +          - clang-10
>>             - libaio-dev
>>             - libattr1-dev
>>             - libbrlapi-dev
>> @@ -303,7 +304,7 @@ jobs:
>>         env:
>>           - TEST_CMD="make check-unit"
>>           - CONFIG="--disable-containers --disable-tcg --enable-kvm
>> -                  --disable-tools --host-cc=clang --cxx=clang++"
>> +                  --disable-tools --host-cc=clang-10 --cc=clang-10 --cxx=clang++-10"
> 
> I forgot to mention we were missing the --cc= flag, so s390-ccw
> was built with an inconsistent $CC. I might respin this part
> separately.

I think the configure script uses the same compiler as --host-cc for --cc if 
it is not specified. So depending on whether Daniel sets the minimum version 
to 6.3 or 6.0, we either can use this patch or we don't need it at all.

  Thomas