From 161252a84085daad28bbfccd52b6af0926dd7251 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 28 Jul 2020 06:59:20 -0700
Subject: [PATCH] PKG_CHECK_MODULES: Properly check if $pkg_cv_[]$1[]_LIBS
 works

There is no need to check $pkg_cv_[]$1[]_LIBS works if package check
failed.

config/ChangeLog:

	* pkg.m4 (PKG_CHECK_MODULES): Use AC_TRY_LINK only if
	$pkg_failed = no.
---
 config/pkg.m4 | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/config/pkg.m4 b/config/pkg.m4
index 45587e97c8b..7ebf517cd6a 100644
--- a/config/pkg.m4
+++ b/config/pkg.m4
@@ -148,10 +148,12 @@ _PKG_CONFIG([$1][_CFLAGS], [cflags], [$2])
 _PKG_CONFIG([$1][_LIBS], [libs], [$2])
 
 dnl Check whether $pkg_cv_[]$1[]_LIBS works.
-pkg_save_LDFLAGS="$LDFLAGS"
-LDFLAGS="$LDFLAGS $pkg_cv_[]$1[]_LIBS"
-AC_TRY_LINK([],[return 0;], [pkg_failed=no], [pkg_failed=yes])
-LDFLAGS=$pkg_save_LDFLAGS
+if test $pkg_failed = no; then
+  pkg_save_LDFLAGS="$LDFLAGS"
+  LDFLAGS="$LDFLAGS $pkg_cv_[]$1[]_LIBS"
+  AC_TRY_LINK([],[], [], [pkg_failed=yes])
+  LDFLAGS=$pkg_save_LDFLAGS
+fi
 
 m4_define([_PKG_TEXT], [Alternatively, you may set the environment variables $1[]_CFLAGS
 and $1[]_LIBS to avoid the need to call pkg-config.