Re: Segmentation fault when compiling m4 1.4.18

[re-adding the lists with permission]

On 05/23/2018 05:47 PM, Eve Armstrong wrote:
> Hi Eric -
> 
>> Is it okay if I post your question on public lists?
> Yes, absolutely.
> 
>> If you are using Cygwin, why not just use Cygwin's pre-built m4, instead
> of rebuilding it yourself?
> So sorry, I am ignorant: cygwin has a pre-built m4?

Yes. 
https://cygwin.com/cgi-bin2/package-cat.cgi?file=x86_64%2Fm4%2Fm4-1.4.18-1&grep=m4.exe

>  I am doubting that
> this is the case, because I need m4 in order to install GNU's autoconf,
> which requires m4.  And the autoconf installation fails to detect m4.

Cygwin also has pre-built autoconf. 
https://cygwin.com/cgi-bin2/package-grep.cgi?grep=autoconf&arch=x86_64

> 
>> Also, cygwin now ships with a newer gcc, so even if gcc 4.9.3 segfaults,
> it may be that upgrading your
>> cygwin installation will get a compiler that no longer has the bug.
> I may try that.  Thank you.

gcc 4.9.3 is ancient; cygwin currently ships with gcc 7.3.0: 
https://cygwin.com/cgi-bin2/package-grep.cgi?grep=gcc.exe&arch=x86_64

but if your compiler bug still persists, then emailing [email protected] 
is the place to report your compilation problems.

> 
> Would compiling manually - i.e. executing gcc commands on the command line
>> - be likely to help?  If so, might you point me to
>>
> 
>> No. Make is invoking gcc commands on the command line on your behalf; but
> if gcc has a bug, then that
>> bug will trigger whether you type the command or whether make types the
> command on your behalf.
> I see.  Okay.  Thank you.
> 

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