Talk:c/preprocessor/conditional

Comprehension of C DR412/CWG1955

I think that C DR412/CWG1955 requires that skill controlling directives are still processed, but not makes failed #elif's unprocessed. But I'm not quite sure that my comprehension is right after having seen Cubbi's.

I changed the contents of DR lists (and applied the issues to C89/C++98). Please revert the change if my comprehension is wrong.

--Fruderica (talk) 06:47, 26 November 2020 (PST)

Consider

Run this code

#if 1
#elif #%&*?
#endif

Run this code

#if 1
#else
# if #%&*?
# endif
#endif

GCC already implemented the DR, and apparently it thinks both are valid. -- D41D8CD98F (talk) 19:16, 26 November 2020 (PST)

I've got it. Thank you very much. --Fruderica (talk) 21:03, 26 November 2020 (PST)