From 4ab41404cb85684125d73977cadebf83bbc246f5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= <remi@remlab.net>
Date: Sat, 22 Jan 2022 11:34:38 +0200
Subject: [PATCH] opengl: missing library check

Traditionally the presence of the header file was not considered
sufficient, though this was somewhat forgotten with the prevalence of
pkg-config.

However most libraries have portable headers, while the shared library
is platform-dependent. It is common for the header to be present while
the library is absent with "multilib" installations (i.e. Linux
installation with multiple architectures).

Downloaded from upstream commit:
https://code.videolan.org/videolan/vlc/-/commit/4ab41404cb85684125d73977cadebf83bbc246f5

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
---
 configure.ac | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index 2f50808d597..0d57fadbf8b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3169,7 +3169,6 @@ have_gl="no"
 PKG_CHECK_MODULES([GL], [gl], [
   have_gl="yes"
 ], [
-  AC_MSG_CHECKING([for OpenGL])
   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #ifdef _WIN32
 # include <GL/glew.h>
@@ -3179,13 +3178,17 @@ PKG_CHECK_MODULES([GL], [gl], [
     [int t0 = GL_TEXTURE0;]])
   ], [
     GL_CFLAGS=""
-    have_gl="yes"
     AS_IF([test "${SYS}" != "mingw32"], [
-      GL_LIBS="-lGL"
+      AC_CHECK_LIB([GL], [glTexture2D], [
+        have_gl="yes"
+        GL_LIBS="-lGL"
+      ])
     ], [
+      have_gl="yes"
       GL_LIBS="-lopengl32"
     ])
   ])
+  AC_MSG_CHECKING([for OpenGL])
   AC_MSG_RESULT([${have_gl}])
 ])
 AM_CONDITIONAL([HAVE_GL], [test "${have_gl}" = "yes"])
-- 
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