Consistent autoconf version

[David DeHaven]

>> Hi,
>> 
>> Sorry if this has come up before, but I cannot find anything in the archives.
>> 
>> Is it possible to agree an autoconf version to use to generate the checked in generated-configure.sh?
>> 
>> I recently had to merge, and regenerate this file, and found versions that were generated with 2.67, 2.68, and 2.69. Using such different versions makes it nearly impossible to see the relevant diffs in generated-configure.sh. While using the same version greatly, but not completely, simplifies the number of changes.
>> 
>> Is there any reason why not to agree a specific version?
> 
> My understanding was it is difficult to use a non-standard version on some (most?) platforms. Most people would probably balk at having to use any version other than that installed by default on their system. Alternatively, if we want a specific version we could mandate that the checked in generated-configure.sh be pushed by a project owner with access to the "official" version. To my knowledge there's only been one buggy (due to buggy autoconf which generated it) generated-configure.sh been checked in. The diffs are annoying but in theory you're not really supposed to read generated-configure.sh, instead you should be reviewing the autoconf inputs which generate it.

If autoconf is a prerequisite for building, why not just leave generated-configure.sh as a generated file rather than in SCM? I understand it lengthens the build time a bit, but unless you're tweaking the build system you only need to run configure sparingly.

-DrD-