The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=4309f9f2347e05bf995dad89d7c21b0149d35b54
commit 4309f9f2347e05bf995dad89d7c21b0149d35b54 Author: Martin Oliveira <[email protected]> AuthorDate: 2023-09-12 20:31:00 +0000 Commit: Warner Losh <[email protected]> CommitDate: 2024-02-03 04:05:49 +0000 include/math.h: fix warning with -Wconversion The way the __fp_type_select macro uses the _Generic expression causes gcc to throw a warning on valid code if the -Wconversion flag is used. For example, consider the following program: #include <math.h> int main() { double x = 1.0; isnan(x); return 0; } which throws a warning: $ gcc -Wconversion a.c a.c:5:15: warning: conversion from 'double' to 'float' may change value [-Wfloat-conversion] 5 | isnan(x); | ^ This happens because the functions are invoked inside of the _Generic. Looking at the example of _Generic in the C11 specification, one sees that the parameters are outside of the _Generic expression (see page 79 here: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf). Reference: https://stackoverflow.com/a/68309379 Signed-off-by: Martin Oliveira <[email protected]> Reviewed by: imp Pull Request: https://github.com/freebsd/freebsd-src/pull/841 --- lib/msun/src/math.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/msun/src/math.h b/lib/msun/src/math.h index 0e09fca72ea3..5fc359ead158 100644 --- a/lib/msun/src/math.h +++ b/lib/msun/src/math.h @@ -76,9 +76,9 @@ extern const union __nan_un { #if __STDC_VERSION__ >= 201112L || __has_extension(c_generic_selections) #define __fp_type_select(x, f, d, ld) __extension__ _Generic((x), \ - float: f(x), \ - double: d(x), \ - long double: ld(x)) + float: f, \ + double: d, \ + long double: ld)(x) #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus) #define __fp_type_select(x, f, d, ld) __builtin_choose_expr( \ __builtin_types_compatible_p(__typeof(x), long double), ld(x), \
