Re: gdb-patches RFA: Fix pascal behavior for class fields

[Pedro Alves <palves at redhat dot com>]

On 01/08/2015 02:15 PM, Pierre Muller wrote:
> For gpc mailing list:
> this email comes as a follow-up of this bug report
> https://sourceware.org/bugzilla/show_bug.cgi?id=17815
> 
> The start of the thread can be found at:
> https://sourceware.org/ml/gdb-patches/2015-01/msg00164.html
> 
> Pedro asked:
>>>> How about adding this to the test suite?
>>>
>>>
>>>   The whole testsuite/gdb.pascal is almost empty,
>>> I never invested time to develop it :(
>>>
>>>   At the time I started it, GPC (the GNU pascal compiler)
>>> was still active, but development apparently
>>> stopped since quite some time.
>>>
>>>   I am unable to install GPC, which means that I cannot test it.
>>> Would a testsuite that supports only Free Pascal be acceptable?
>>
>> Do you actually mean, whether it's ok for a new
>> test (not test suite) to go in untested on GPC?  It certainly is.
>> Better test on FPC than nowhere.  :-)
>   That is indeed what I meant.
>  
>> AFAICS, the tests themselves don't really care which compiler
>> is in use other than for marking xfails; you just call
>> gdb_compile_pascal,
>> and that works with either.  That's my impression from quickly
>> skimming testsuite/lib/pascal.exp.
> 
>   The problem is that GPC and Free Pascal support several
> pascal 'dialects'. But this requires command line options.
> 
>   The -Mobjfpc option is required for Free Pascal compiler
> to understand class type definition, but is rejected in default mode.
> 
>   I expect GNU GPC to also reject class in 'normal' mode...
> Maybe someone on the gpc mailing list knows if classes are supported
> by GPC and if it requires a special compiler option.

I'd suggest adding support for a new option to
gdb_compile_pascal, like "objfpc", so you'd compile
the test with:

 if {[gdb_compile_pascal ... executable [list debug objfpc]] != "" } {
     untested $testfile.exp
     return -1
 }

You'd teach fpc_compile about the new option:

proc fpc_compile {source dest type options} {
...
    foreach i $options {
...
        } elseif { $i == "objfpc" } {
           append add_flags " -Mobjfpc"
        }
...
    }


Someone that cares about testing with GNU GPC would then
do the equivalent to gpc_compile, if anything is necessary.
If gpc simply fails to compile the test, it's no biggie,
as gdb_compile_pascal returns false, and the test is
skipped with "untested".

There may be a more generic and common name for the mode,
like "obj-pascal" or something, but I wouldn't know.

Thanks,
Pedro Alves