Re: Make check - test-vasprintf-posix failure - darwin12 - macos

[Eric Blake]

On Mon, Mar 28, 2022 at 12:51:10AM +0000, Gaëtan HERFRAY wrote:
> Hello,
> 
> I'm trying to compile M4-1.4.19 on macOS, and I ran :
> 
> ./configure
> make
> make check
> 
> Actually, make check is failing on test-vasprintf-posix.

Thanks for the report.  This test is maintained by gnulib, so other
projects may see the same failure in that test.  Or it may have been
fixed in the meantime (I still need to release an updated version of
m4).

> After investigating, I found that they are 3 tests that are failing, about
> pseudo denormal (you can find the four tests by looking for "{ LDBL80_WORDS
> (0x0000, 0x83333333, 0x00000000) }".
> 
> Only the first one pass, the three next are failing.
> 
> First question: are those tests important?

They are important to gnulib, as it helps find places where we still
need to work around platform bugs.  But they are less important to m4,
which does not output floating point numbers, and therefore does not
need to worry about printf() bugs in dealing with pseudo-denormal bit
values.

> 
> For help with investigation, I found that by replacing 0x83333333
> to 0x63333333 will make the tests pass, but I don't know what the impacts
> are as I'm absolutely not a C developer.
> 
> Note:
> 
> After reading here:
> https://lists.gnu.org/archive/html/bug-m4/2013-06/msg00000.html I also
> tried running ./configure gl_cv_func_printf_directive_a=no, but no chance
> of making it working.
> 
> The only solution I found is by commenting the three last tests
> about Pseudo-Denormal directly in tests/test-vasprintf-posix.c
> 
> Thanks a lot

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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