pre_src_configure() {
	# Avoid noise from intentional ones...
	export ac_cv_c_undeclared_builtin_options="none needed"
	export ac_cv_func___fpurge="yes"
	export ac_cv_func_fpurge="yes"
	export ac_cv_have_decl_fpurge="no"
	export ac_cv_header_sys_types_h_makedev="no"
	export gl_cv_func_fpurge_works="no"
	export gl_cv_compiler_check_decl_option="-Werror=implicit-function-declaration"
	export gl_cv_minmax_in_limits_h="no"

	cat <<- EOF > "${T}"/clang
	#!/usr/bin/env bash

	# Need > /dev/null for sys-libs/musl
	clang-15 -Wno-unused-command-line-argument -Wno-error=implicit-function-declaration -Wno-error=implicit-int -Wno-error=strict-prototypes \$@ 2>&1 | ansifilter | sed \
		-e "s:14.0.6:14.ignoreme:g" \
		-e "s:15.0.0:14.ignoreme:g" \
		-e "s:conftest-.*\.o:conftest.o:g" \
		-e "s_conftest\.c\:[0-9]\+\:[0-9]\+_ignoreme_g" \
		-e '/[0-9]\+ \(warning\|error\) generated/d' | tee -a "${T}"/clang14.log > /dev/null

	clang-15 -Wno-unused-command-line-argument -Werror=implicit-function-declaration -Werror=implicit-int -Werror=strict-prototypes \$@ 2>&1 | ansifilter | sed \
		-e "s:14.0.6:14.ignoreme:g" \
		-e "s:15.0.0:14.ignoreme:g" \
		-e "s:15:14:g" \
		-e "s:conftest-.*\.o:conftest.o:g" \
		-e "s_conftest\.c\:[0-9]\+\:[0-9]\+_ignoreme_g" \
		-e '/[0-9]\+ \(warning\|error\) generated/d' | tee -a "${T}"/clang15.log > /dev/null
	x=\${PIPESTATUS}

	# Non-Autoconf configure scripts might try to parse stderr/stdout, so just run
	# it again...
	if [[ -f configure ]] && ! grep -q "#.*Generated by Autoconf" configure ; then
		clang-15 \$@
	else
		exit \${x[0]}
	fi
	EOF

	chmod +x "${T}"/clang

	export OLD_PATH="${PATH}"
	export PATH="${T}:${PATH}"
}

post_src_configure() {
	if [[ -z ${OLD_PATH} ]] ; then
		return
	fi

	export PATH="${OLD_PATH}"

	if [[ -f "${T}"/clang14.log ]] ; then
		mkdir -p /var/tmp/clang/${CATEGORY}/${PF}
		cp -rv "${T}"/clang{14,15}.log /var/tmp/clang/${CATEGORY}/${PF}
		diff -ruN "${T}"/clang{14,15}.log > /var/tmp/clang/${CATEGORY}/${PF}/clang.diff
	fi
}