PR fortran/9038, a regression in 3.3/3.4 with respect to 3.2.

[Toon Moene]

[  I'll take Paul out of the loop ]

Neil Booth wrote:

> Toon Moene wrote:

>>Definitely.  So the question is: how do we prevent the passing on of 
>>this switch to the rest of cc1 in case cc1 is called with the -E switch ....
>>
>>In f771, we just return -1 from ffe_decode_option - does that mean that 
>>setting `result' to -1 in c_common_decode_option will have the same effect ?

> I don't understand the problem.  I thought the original problem was that
> the C front end doesn't accept the switch.  So I tell you how to get it
> to accept it.  Then you say the problem is that the C front end accepts
> the switch?
> 
> The correct place to modify C front end options is the big table in
> c-opts.c; nowhere else.

OK - I start to see the mismatch in our descriptions what the problem is.

Prior to 3.3, preprocessing Fortran source (e.g., when the source file's 
name ends in .F) was taken care of by a separate preprocessor that 
*only* performed preprocessing.  So any option that didn't make sense to 
preprocessing was "automagically" ignored by this program.

Nowadays - i.e., from 3.3 onwards - preprocessing is performed by cc1 -E.

That in itself wouldn't be a problem, if not every option that's passed 
to g77 gets passed to *both* cc1 -E and f771 by virtue of the way specs 
is written.

f771 knows that it shouldn't hand down -ffixed-form and 
-ffixed-line-length-<blah> options to other option processors, because 
they only have a definite meaning to the Fortran front end, and would 
give rise to spurious "unknown register: form" messages if not stopped 
short in the option processing for Fortran.

Now what I want to accomplish is to teach cc1 the same.  In fact, it 
would only be necessary to teach cc1 if -E is specified, but it probably 
won't hurt to simply prevent passing -ffixed-form and 
-ffixed-line-length-<blah> downwards to other option processors.

Hope this explanation helps,

-- 
Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290
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