Re: Regression: git no longer works with musl libc's regex impl

From: Ramsay Jones <ramsay@ramsayjones.plus.com>
Date: Oct 6, 2016, 22:42 UTC
Message-ID: <20336ac7-a494-d725-f928-834b1b3194fe@ramsayjones.plus.com>
In-Reply-To: <CACBZZX4XPqZauD_M_ieOwVauT1fi3MQb4+6taELQaRG9M-Kz_w@mail.gmail.com>

On 06/10/16 20:18, Ævar Arnfjörð Bjarmason wrote:

Show 14 quoted lines

> On Tue, Oct 4, 2016 at 6:08 PM, Johannes Schindelin
> <Johannes.Schindelin@gmx.de> wrote:
>> As to making NO_REGEX conditional on REG_STARTEND: you are talking about
>> apples and oranges here. NO_REGEX is a Makefile flag, while REG_STARTEND
>> is a C preprocessor macro.
>>
>> Unless you can convince the rest of the Git developers (you would not
>> convince me) to simulate autoconf by compiling an executable every time
>> `make` is run, to determine whether REG_STARTEND is defined, this is a
>> no-go.
> 
> But just to clarify, does anyone have any objection to making our
> configure.ac compile a C program to check for this sort of thing?
> Because that seems like the easiest solution to this class of problem.

Err, you do know that we already do that, right?

[see commit a1e3b669 ("autoconf: don't use platform regex if it lacks REG_STARTEND", 17-08-2010)]

In fact, if you run the auto tools on cygwin, you get a different setting for NO_REGEX than via config.mak.uname. Which is why I don't run configure on cygwin. :-D

[The issue is exposed by t7008-grep-binary.sh, where the cygwin native regex library matches '.' in a pattern with the NUL character. ie the test_expect_failure test passes.]

ATB, Ramsay Jones