RE: Currently, CVS setup.exe does not compile, due to warnings with 'warnings as errors' in effect. How best to change code to avoid warnings?

RE: Currently, CVS setup.exe does not compile, due to warnings with 'warnings as errors' in effect. How best to change code to avoid warnings?

[Robert Collins]

> -----Original Message-----
> From: Max Bowsher [mailto:maxb@ukf.net] 

> What do the experts think?

Hmm, does C++ support the same feature? If not then an ifdef __cplusplus
might do it.

Rob

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w32api bugfix (was: Currently, CVS setup.exe does not compile, due to warnings with 'warnings as errors' in effect. How best to change code to avoid warnings?)

[Max Bowsher]

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> Hmm, does C++ support the same feature? If not then an ifdef __cplusplus
> might do it.

> Rob

Unfortunately not - the problem is the differing interpretation of the line
'typedef int (WINAPI *FARPROC)();' in 3 sets of circumstances:

1) C++
        'int proc();' and 'int proc(void);' are synonyms. No problem.

2) C, -Wstrict-prototypes NOT in effect
        'int proc();' means: use no compiler type checking for the
parameters if proc
        'int proc(void);' means: proc takes no parameters

3) C, -Wstrict-prototypes in effect
        'int proc();' means: ditto AND causes a warning (which, since setup
is compiled with 'warnings as errors' on, stops the build)
        'int proc(void);' means: ditto

Summary:
The construct 'typedef int (WINAPI *FARPROC)();' in w32api causes an error
with -Wstrict-prototypes -Werror. This can be worked around by adding 'void'
in the empty brackets.
Downside:
This breaks C code where people were using the w32api types FARPROC,
NEARPROC, PROC, to call procedures without typechecking the arguments. I
think this is totally irrelevant, as deliberately bypassing the compiler
type checking is very silly, and I doubt anyone does that anymore.

Anyway, before I go submitting a patch which breaks backward compatibility,
even in such a rare and unused case, I want to raise this issue here.


Max.

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Currently, CVS setup.exe does not compile, due to warnings with 'warnings as errors' in effect. How best to change code to avoid warnings?

[Max Bowsher]

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Currently, CVS setup.exe does not compile, due to warnings with 'warnings as
errors' in effect. How best to change code to avoid warnings?

Warning in winsup/bz2lib/bzlib.c:

static char *bzerrorstrings[] = {
       "OK"
....

This requires the insertion of a const qualifier. I'm mentioning this in
passing - this change is obviously correct. The main point is the next
warning:

Warning in winsup/w32api/include/windef.h:

typedef int (WINAPI *FARPROC)();
typedef int (WINAPI *NEARPROC)();
typedef int (WINAPI *PROC)();

Since -Wstrict-prototypes is in effect, gcc won't accept empty sets of
brackets to declare a function. Adding void between the brackets solves the
problem _here_, but is this a good thing to do, given that it would break
code using C's unchecked parameters feature with these types?

What do the experts think?


Max.

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