Ping.
> Fixes c++/91318.
>
> libcpp/ChangeLog:
>
> 2019-08-06 Piotr Henryk Dabrowski <p...@phd.re>
>
> PR c++/91318
> * include/cpplib.h: Added cpp_define_unused(),
> cpp_define_formatted_unused()
> * directives.c: Likewise.
>
> gcc/c-family/ChangeLog:
>
> 2019-08-06 Piotr Henryk Dabrowski <p...@phd.re>
>
> PR c++/91318
> * c-cppbuiltin.c: c_cpp_builtins_optimize_pragma(): use
> cpp_define_unused()
>
>
> diff --git a/gcc/c-family/c-cppbuiltin.c b/gcc/c-family/c-cppbuiltin.c
> index d389f8ca4a0..47d0cefb85a 100644
> --- a/gcc/c-family/c-cppbuiltin.c
> +++ b/gcc/c-family/c-cppbuiltin.c
> @@ -576,41 +576,41 @@ c_cpp_builtins_optimize_pragma (cpp_reader *pfile, tree
> prev_tree,
> /* Other target-independent built-ins determined by command-line
> options. */
> if (!prev->x_optimize_size && cur->x_optimize_size)
> - cpp_define (pfile, "__OPTIMIZE_SIZE__");
> + cpp_define_unused (pfile, "__OPTIMIZE_SIZE__");
> else if (prev->x_optimize_size && !cur->x_optimize_size)
> cpp_undef (pfile, "__OPTIMIZE_SIZE__");
>
> if (!prev->x_optimize && cur->x_optimize)
> - cpp_define (pfile, "__OPTIMIZE__");
> + cpp_define_unused (pfile, "__OPTIMIZE__");
> else if (prev->x_optimize && !cur->x_optimize)
> cpp_undef (pfile, "__OPTIMIZE__");
>
> prev_fast_math = fast_math_flags_struct_set_p (prev);
> cur_fast_math = fast_math_flags_struct_set_p (cur);
> if (!prev_fast_math && cur_fast_math)
> - cpp_define (pfile, "__FAST_MATH__");
> + cpp_define_unused (pfile, "__FAST_MATH__");
> else if (prev_fast_math && !cur_fast_math)
> cpp_undef (pfile, "__FAST_MATH__");
>
> if (!prev->x_flag_signaling_nans && cur->x_flag_signaling_nans)
> - cpp_define (pfile, "__SUPPORT_SNAN__");
> + cpp_define_unused (pfile, "__SUPPORT_SNAN__");
> else if (prev->x_flag_signaling_nans && !cur->x_flag_signaling_nans)
> cpp_undef (pfile, "__SUPPORT_SNAN__");
>
> if (!prev->x_flag_errno_math && cur->x_flag_errno_math)
> cpp_undef (pfile, "__NO_MATH_ERRNO__");
> else if (prev->x_flag_errno_math && !cur->x_flag_errno_math)
> - cpp_define (pfile, "__NO_MATH_ERRNO__");
> + cpp_define_unused (pfile, "__NO_MATH_ERRNO__");
>
> if (!prev->x_flag_finite_math_only && cur->x_flag_finite_math_only)
> {
> cpp_undef (pfile, "__FINITE_MATH_ONLY__");
> - cpp_define (pfile, "__FINITE_MATH_ONLY__=1");
> + cpp_define_unused (pfile, "__FINITE_MATH_ONLY__=1");
> }
> else if (prev->x_flag_finite_math_only && !cur->x_flag_finite_math_only)
> {
> cpp_undef (pfile, "__FINITE_MATH_ONLY__");
> - cpp_define (pfile, "__FINITE_MATH_ONLY__=0");
> + cpp_define_unused (pfile, "__FINITE_MATH_ONLY__=0");
> }
> }
>
> diff --git a/libcpp/directives.c b/libcpp/directives.c
> index ddf8979d513..9a774c9ed04 100644
> --- a/libcpp/directives.c
> +++ b/libcpp/directives.c
> @@ -2392,6 +2392,15 @@ cpp_define (cpp_reader *pfile, const char *str)
> run_directive (pfile, T_DEFINE, buf, count);
> }
>
> +/* Like cpp_define, but does not warn about unused macro. */
> +void
> +cpp_define_unused (cpp_reader *pfile, const char *str)
> +{
> + unsigned char warn_unused_macros = CPP_OPTION (pfile,
> warn_unused_macros);
> + CPP_OPTION (pfile, warn_unused_macros) = 0;
> + cpp_define (pfile, str);
> + CPP_OPTION (pfile, warn_unused_macros) = warn_unused_macros;
> +}
>
> /* Use to build macros to be run through cpp_define() as
> described above.
> @@ -2411,6 +2420,20 @@ cpp_define_formatted (cpp_reader *pfile, const char
> *fmt, ...)
> free (ptr);
> }
>
> +/* Like cpp_define_formatted, but does not warn about unused macro. */
> +void
> +cpp_define_formatted_unused (cpp_reader *pfile, const char *fmt, ...)
> +{
> + char *ptr;
> +
> + va_list ap;
> + va_start (ap, fmt);
> + ptr = xvasprintf (fmt, ap);
> + va_end (ap);
> +
> + cpp_define_unused (pfile, ptr);
> + free (ptr);
> +}
>
> /* Slight variant of the above for use by initialize_builtins. */
> void
> diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
> index a645f8136a6..8d3f9082601 100644
> --- a/libcpp/include/cpplib.h
> +++ b/libcpp/include/cpplib.h
> @@ -1052,8 +1052,12 @@ extern cppchar_t cpp_host_to_exec_charset (cpp_reader
> *, cppchar_t);
> /* Used to register macros and assertions, perhaps from the command line.
> The text is the same as the command line argument. */
> extern void cpp_define (cpp_reader *, const char *);
> +extern void cpp_define_unused (cpp_reader *, const char *);
> extern void cpp_define_formatted (cpp_reader *pfile,
> const char *fmt, ...) ATTRIBUTE_PRINTF_2;
> +extern void cpp_define_formatted_unused (cpp_reader *pfile,
> + const char *fmt,
> + ...) ATTRIBUTE_PRINTF_2;
> extern void cpp_assert (cpp_reader *, const char *);
> extern void cpp_undef (cpp_reader *, const char *);
> extern void cpp_unassert (cpp_reader *, const char *);
>
