configure: Drop broken workarounds for missing pkg-config

Any reasonably-modern system should have versions of things like OpenGL
libraries installed with pkg-config libraries.

Regardless, the checks we had in place here for missing gl.pc files
were untested and obviously not very useful, (they didn't actually
look around anywhere for GL headers nor for GL libraries).

We're better off not even pretending to be able to find things without
pkg-config.

diff --git a/configure b/configure
index c59820fee7cbd6f571604689505c6531e7f4d84e..77fedba4fb0e8f088e9ae05b2c148342067ba84f 100755 (executable)
--- a/configure
+++ b/configure
@@ -281,16 +281,9 @@ if pkg-config --exists gl; then
     gl_cflags=$(pkg-config --cflags gl)
     gl_ldflags=$(pkg-config --libs gl)
 else
-    printf "#include <GL/gl.h>\nint main(void){return 0;}\n" > gl-minimal.c
-    if ${CC} -o gl-minimal gl-minimal.c > /dev/null 2>&1
-    then
-       printf "Yes.\n"
-       have_gl=1
-    else
-       printf "No.\n"
-       errors=$((errors + 1))
-    fi
-    rm -f gl-minimal gl-minimal.c
+    printf"No.\n"
+    have_gl=0
+    errors=$((errors + 1))
 fi
 
 printf "Checking for GL window-system-binding headers:\n"
@@ -309,6 +302,10 @@ else
 fi
 rm -f glx-minimal glx-minimal.c
 
+if [ $have_gl_winsys -eq 0 ]; then
+    errors=$((errors + 1))
+fi
+
 printf "       Checking for X11... "
 have_x11=No
 if pkg-config --exists x11; then
@@ -328,20 +325,8 @@ if pkg-config --exists egl; then
     egl_cflags=$(pkg-config --cflags egl)
     egl_ldflags=$(pkg-config --libs egl)
 else
-    printf "#include <EGL/egl.h>\nint main(void){return 0;}\n" > egl-minimal.c
-    if ${CC} -o egl-minimal egl-minimal.c ${gl_cflags} > /dev/null 2>&1
-    then
-       printf "Yes.\n"
-       have_gl_winsys=1
-       have_egl=1
-    else
-       printf "No.\n"
-    fi
-    rm -f egl-minimal egl-minimal.c
-fi
-
-if [ $have_gl_winsys -eq 0 ]; then
-    errors=$((errors + 1))
+    printf "No.\n"
+    have_egl=No
 fi
 
 printf "int main(void){return 0;}\n" > minimal.c