[Bug c/113776] [14 regression] postgresql-16.1 build failure with -Werror=vla in configure test since r14-8641

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113776

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Joseph Myers <jsm28@gcc.gnu.org>:

https://gcc.gnu.org/g:bfd72bb44eca83b0db2b0bab895f27a8a44247a2

commit r14-8874-gbfd72bb44eca83b0db2b0bab895f27a8a44247a2
Author: Joseph Myers <josmyers@redhat.com>
Date:   Thu Feb 8 01:34:09 2024 +0000

    c: Fix boolean conversion of floating constant as integer constant
expression [PR113776]

    My fix for bug 111059 and bug 111911 caused a conversion of a floating
    constant to boolean to wrongly no longer be considered an integer
    constant expression, because logic to insert a NOP_EXPR in
    c_objc_common_truthvalue_conversion for an argument not an integer
    constant expression itself now took place after rather than before the
    conversion to bool.  In the specific case of casting a floating
    constant to bool, the result is an integer constant expression even
    though the argument isn't (build_c_cast deals with ensuring that casts
    to integer type of anything of floating type more complicated than a
    single floating constant don't get wrongly treated as integer constant
    expressions even if they fold to constants), so fix the logic in
    c_objc_common_truthvalue_conversion to handle that special case.

    Bootstrapped with no regressions for x86_64-pc-linux-gnu.

            PR c/113776

    gcc/c
            * c-typeck.cc (c_objc_common_truthvalue_conversion): Return an
            integer constant expression for boolean conversion of floating
            constant.

    gcc/testsuite/
            * gcc.dg/pr113776-1.c, gcc.dg/pr113776-2.c, gcc.dg/pr113776-3.c,
            gcc.dg/pr113776-4.c: New tests.