Re: [PULL 04/31] build-system: clean up TCG/TCI configury

[Philippe Mathieu-Daudé]

On 2/6/21 7:01 PM, Philippe Mathieu-Daudé wrote:
> On 1/23/21 3:31 PM, Paolo Bonzini wrote:
>> Make CONFIG_TCG_INTERPRETER a Meson option, and enable TCI (though with
>> a warning) if the host CPU is unsupported, making it more similar to
>> other --enable-* options.
>>
>> Remove TCG-specific include paths from !CONFIG_TCG builds.
>>
>> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>> ---
>>  configure         | 11 +++--------
>>  disas/meson.build |  2 --
>>  meson.build       | 46 +++++++++++++++++++++++++---------------------
>>  meson_options.txt |  2 ++
>>  4 files changed, 30 insertions(+), 31 deletions(-)
> 
> I spent 2h bisecting until:
> 
> 23a77b2d18b84e410478e88f11c54911f7a649fc is the first bad commit
> commit 23a77b2d18b84e410478e88f11c54911f7a649fc
> Author: Paolo Bonzini <pbonzini@redhat.com>
> Date:   Mon Dec 14 12:01:45 2020 +0100
> 
>     build-system: clean up TCG/TCI configury
> 
>     Make CONFIG_TCG_INTERPRETER a Meson option, and enable TCI (though with
>     a warning) if the host CPU is unsupported, making it more similar to
>     other --enable-* options.
> 
>     Remove TCG-specific include paths from !CONFIG_TCG builds.
> 
>     Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> 
> to realize I need to re-bisect from here now including:
> 
> commit c6fbea47664466e526e40300568324ef77e5f2cc
> Author: Richard Henderson <richard.henderson@linaro.org>
> Date:   Sun Jan 24 11:10:55 2021 -1000
> 
>     configure: Fix --enable-tcg-interpreter
> 
>     The configure option was backward, and we failed to
>     pass the value on to meson.
> 
>     Fixes: 23a77b2d18b ("build-system: clean up TCG/TCI configury")
>     Tested-by: Stefan Weil <sw@weilnetz.de>
>     Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
>     Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>     Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
>     Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>     Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

>From a buildir configured *before* 23a77b2d18b84, checking out
*after* c6fbea476644 (5b19cb63d9d actually, pull-tcg-20210205
merged today) I get:

[352/396] Compiling C object
libqemu-hppa-linux-user.fa.p/target_hppa_translate.c.o
In file included from /home/philmd/qemu/include/tcg/tcg-op.h:28,
                 from ../target/hppa/translate.c:25:
/home/philmd/qemu/include/tcg/tcg.h:35:10: fatal error: tcg-target.h: No
such file or directory
   35 | #include "tcg-target.h"
      |          ^~~~~~~~~~~~~~
compilation terminated.

When starting in a new empty directory, it works. I don't understand
because there are no generated files involved (similarly to commit
0572d6cd29d).

Note for later: Better merge buildsys fixes sooner rather than later,
as it ease bisections.