lib/raster3d: fix -Wdeprecated-non-prototype compiler warnings #2901
Conversation
nilason
force-pushed
the
fix_more_Wdeprecated-non-prototype_v2
branch
from
ae0ed52 to
c308c96
Compare
Split read and write functions, using function pointers do not work as the parameters has deviating qualifiers (const vs non-const).
nilason
force-pushed
the
fix_more_Wdeprecated-non-prototype_v2
branch
from
c308c96 to
76bc4d1
Compare
|
I would welcome review on this one. This PR together with #3344 are the last fixes to prepare GRASS code to work with and comply to C23 standard. |
|
I've read about this C prototype discussion when Clang implemented it, and I'm favorable for it. From your changes, I could find one that I fully understood (the one that added a void instead of nothing in the prototype). I understand that it could only be breaking for users that would use our software as a library, and would have been using it potentially inappropriately. Including in 8.4 is appropriate then. I also understand the better warnings that the compiler can emit, so it's a bigger win. As for the other lines, I'm not sure I understand the consequences of it, so I'm not sure how to review it confidently. |
It is not a Clang-thing, but a C23 standard feature (for background see eg. https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2841.htm). It is a step to modernise the code, enable it to build with C23+ compilers. We now require C11 conformance, but that may change, and this PR doesn't break anything for C11. The more immediate cause for this PR is better described in #2891. These are the compiler warnings issued:
If you don't feel comfortable with reviewing it, I won't blame you for not to :-). But studying the "old" code is quite educational. Pretty clever use of function pointers. |
|
I'm ok with the change, and I tested with clang 14 on FreeBSD 14, and it's OK. |
@lbartoletti Thanks! |
There was a problem hiding this comment.
I was confused for a minute whether there is some new function prototype thing, but the sentence from the linked document clarified it for me:
Submission Date: 2021-10-10
...
Function declarators without prototypes have been an obsolescent feature since the very first ISO C standard. 33 years of advance warning should be enough.
:-)))
And FYI, gcc14 will raise error on old C code: https://gcc.gnu.org/gcc-14/porting_to.html#c |
…#2901) Split read and write functions, using function pointers do not work as the parameters has deviating qualifiers (const vs non-const). It does introduce some repetitive code, but do not remove the correctly used const qualifiers in the Rast3d_key_set_double() and similar functions. Note: the "write" part of Rast3d_readWriteWindow() in windowio.c is never used and therefore removed. A write function is easily implemented if needed.
Split read and write functions, using function pointers do not work as the parameters has deviating qualifiers (const vs non-const).
This is a, perhaps preferable, alternative to #2891.
It does introduce some repetitive code, but do not remove the correctly used const qualifiers in the
Rast3d_key_set_double()and similar functions.Note: the "write" part of
Rast3d_readWriteWindow()inwindowio.cis never used and therefore removed. A write function is easily implemented if needed.