[Qemu-devel] Re: [PATCH] configure: fix breakage of --extra-{cflags, ldflags}

[Jan Kiszka <jan.kiszka@siemens.com>]

Juan Quintela wrote:
> Jan Kiszka <jan.kiszka@siemens.com> wrote:
>> Nathan Froyd wrote:
>>> Commit e3fc14c3a1a77a1cda669a3e16f1f6b82577e4ec broke the use of
>>> --extra-{cflags,ldflags} in the case where those flags were necessary
>>> for bits of configure to succeed.  For instance, if you did:
>>>
>>>   configure [...] --extra-cflags=-I/path/to/zlib/headers \
>>>     --extra-ldflags=-L/path/to/zlib/libraries
>>>
>>> prior to the above commit, the paths would go into CFLAGS and LDFLAGS
>>> for use by the rest of the configure tests.  After the above commit,
>>> that's no longer true, because the EXTRA_{CFLAGS,LDFLAGS} variables are
>>> only used for creating makefiles.
>> Yep, that's true...
>>
>>> Fixed by making sure that EXTRA_{CFLAGS,LDFLAGS} find their way into
>>> {CFLAGS,LDFLAGS}, respectively.
>>>
>>> Signed-off-by: Nathan Froyd <froydnj@codesourcery.com>
>>> ---
>>>  configure |    4 ++--
>>>  1 files changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/configure b/configure
>>> index 0db885b..dd2b1d9 100755
>>> --- a/configure
>>> +++ b/configure
>>> @@ -520,8 +520,8 @@ CFLAGS="$CFLAGS -g -fno-strict-aliasing"
>>>  if test "$debug" = "no" ; then
>>>    CFLAGS="$CFLAGS -O2"
>>>  fi
>>> -CFLAGS="$CFLAGS -Wall -Wundef -Wendif-labels -Wwrite-strings -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls"
>>> -LDFLAGS="$LDFLAGS -g"
>>> +CFLAGS="$CFLAGS $EXTRA_CFLAGS -Wall -Wundef -Wendif-labels -Wwrite-strings -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls"
>>> +LDFLAGS="$LDFLAGS $EXTRA_LDFLAGS -g"
>> ...but now we add the extra flags twice. So please remove the injection
>> into the flags for $config_mak.
> 
> It is still broken.  Thinking of a solution.

Good that someone is more awake than /me. :)

> People wanted EXTRA_CFLAGS to be added at the end of CFLAGS, not in the
> middle.  Trying to find a way that is consistent for everything.
> 
> Could you told in what test do you need extra_cflags?

I think the only consistent solution (besides stopping to re-invent
autotools) is explicitly appending EXTRA_CFLAGS to all tests.

Jan

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