toolchain-funcs.eclass: Add tc-check-min_ver()

Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>

eclass/toolchain-funcs.eclass

@@ -647,6 +647,50 @@ _tc-has-openmp() {
 	return ${ret}
 }
 
+# @FUNCTION: tc-check-min_ver
+# @USAGE: <gcc or clang> <minimum version>
+# @DESCRIPTION:
+# Minimum version of active GCC or Clang to require.
+#
+# You should test for any necessary minimum version in pkg_pretend in order to
+# warn the user of required toolchain changes.  You must still check for it at
+# build-time, e.g.
+# @CODE
+# pkg_pretend() {
+#	[[ ${MERGE_TYPE} != binary ]] && tc-check-min_ver gcc 13.2.0
+# }
+#
+# pkg_setup() {
+#	[[ ${MERGE_TYPE} != binary ]] && tc-check-min_ver gcc 13.2.0
+# }
+# @CODE
+tc-check-min_ver() {
+	do_check() {
+		debug-print "Compiler version check for ${1}"
+		debug-print "Detected: ${2}"
+		debug-print "Required: ${3}"
+		if ver_test ${2} -lt ${3}; then
+			eerror "Your current compiler is too old for this package!"
+			die "Active compiler is too old for this package (found ${1} ${2})."
+		fi
+	}
+
+	case ${1} in
+		gcc)
+			tc-is-gcc || return
+			do_check GCC $(gcc-version) ${2}
+			;;
+		clang)
+			tc-is-clang || return
+			do_check Clang $(clang-version) ${2}
+			;;
+		*)
+			eerror "Unknown first parameter for ${FUNCNAME} - must be gcc or clang"
+			die "${FUNCNAME}: Parameter ${1} unknown"
+			;;
+	esac
+}
+
 # @FUNCTION: tc-check-openmp
 # @DESCRIPTION:
 # Test for OpenMP support with the current compiler and error out with