Some packages may need an adaption with GCC 14

Reference: ​https://gitlab.com/fweimer-rh/fedora-modernc

Expect (5.45.4)

FTBFS with configure: error: could not find source file 'pty_.c'.

Fedora uses ​a patch, but the patch needs to run autoconf. For LFS we can just pass CC="gcc -std=gnu89" to configure.

Libxcrypt (4.4.36)

Fails to probe the <ucontext.h> header: ​https://github.com/besser82/libxcrypt/pull/178

It causes test/explicit-bzero skipped. Not a serious issue and we can ignore.

Bash (5.2.21 + upstream_fixes-1.patch)

Spurious output in config.log: ​https://lists.gnu.org/archive/html/bug-bash/2023-02/msg00000.html

Not really harming, the probing result still happens to be correct.