bug#28906: flymake test different-diagnostic-types fails

[Glenn Morris]

João Távora wrote:

> This appears to be the first test run since the Flymake rewrite that was
> merged into emacs-26, so the test didn't really "begin failing", it just
> didn't exist before that.

Sorry; got fooled by git's unhelpful date fields.

> Anyway, I think there's a good chance that the culprit is gcc version
> 4.8.5 which probably outputs something that Flymake can't recognize as a
> note. 

FWIW, here's the output of "make errors-and-warnings.o":

    cc    -c -o errors-and-warnings.o errors-and-warnings.c
    In file included from errors-and-warnings.c:3:0:
    some-problems.h:3:1: warning: data definition has no type or storage class 
[enabled by default]
     strange;
     ^
    some-problems.h:5:1: error: unknown type name 'sint'
     sint main();
     ^
    errors-and-warnings.c: In function 'main':
    errors-and-warnings.c:9:3: warning: overflow in implicit constant 
conversion [-Woverflow]
       char c = 1000; /* a note and a warning */
       ^
    errors-and-warnings.c:11:8: error: redeclaration of 'c' with no linkage
       char c; if (bla == (void*)3); /* an error, and two warnings */
            ^
    errors-and-warnings.c:9:8: note: previous definition of 'c' was here
       char c = 1000; /* a note and a warning */
            ^
    errors-and-warnings.c:11:19: warning: comparison between pointer and 
integer [enabled by default]
       char c; if (bla == (void*)3); /* an error, and two warnings */


> Is there any chance that Hydra can be upgraded to use a newer gcc, or
> should I skip this test for such gcc versions?

It's not just hydra. Eg RHEL7 still defaults to gcc 4.8, so I'd suggest
skipping it.

> Tips on how to install gcc 4 on debian alongside the system gcc are
> also welcome.

I think you'd have to install it by hand, since it doesn't seem to be in
the Debian repos any more.