Re: FYI, 2.73 slower than 2.72

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On 2026-03-18 22:01, Nick Bowler wrote:
> On Wed, Mar 18, 2026 at 12:57:53PM -0400, Zack Weinberg wrote:
>> Do you happen to remember why we concatenate confdefs.h and the test
>> program, instead of #include-ing confdefs.h from the test program?
> 
> A long time ago C compilations did use #include "confdefs.h" but it was
> changed to resemble the current method in version 2.55 (2002).
> 
> No explicit rationale is given but it was probably done this way to
> improve the logging around compilation failures.

Thanks, then let's ask Akim. Akim, is that why you installed commit 
c4e69deefdc48a44849fd6c1ae4a49811e62f0c1 dated 2002-10-31 into 
lib/autoconf/c.m4's AC_LANG_SOURCE(C)? We're asking because we're 
thinking of going back to the old way of doing things, for efficiency 
reasons. I'm attaching a copy of that old commit for convenience.
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