diff -rupN --no-dereference gdal-3.2.2-fedora/m4/geos.m4 gdal-3.2.2-fedora-new/m4/geos.m4
--- gdal-3.2.2-fedora/m4/geos.m4	2021-03-24 13:44:42.101428816 +0100
+++ gdal-3.2.2-fedora-new/m4/geos.m4	2021-03-24 13:44:42.103428816 +0100
@@ -59,7 +59,9 @@ AC_DEFUN([GEOS_INIT],[
   elif test x"$with_geos" = x"yes" -o x"$with_geos" = x"" ; then
 
     AC_PATH_PROG(GEOS_CONFIG, geos-config, no)
-    ac_geos_config_auto=yes
+    if test x"$with_geos" = x"" ; then
+      ac_geos_config_auto=yes
+    fi
 
   else
 
@@ -140,7 +142,14 @@ AC_DEFUN([GEOS_INIT],[
       )
 
       if test x"$HAVE_GEOS" = "xno"; then
-          GEOS_CFLAGS=""
+        if test $ac_geos_config_auto = "yes" ; then
+          AC_MSG_WARN([GEOS was found on your system, but the library could not be linked. GEOS support disabled.])
+        else
+          AC_MSG_ERROR([GEOS library could not be linked])
+        fi
+
+        GEOS_CFLAGS=""
+
       fi
 
       CFLAGS="${ax_save_CFLAGS}"
@@ -149,6 +158,12 @@ AC_DEFUN([GEOS_INIT],[
 
     fi
 
+  else
+
+    if test $ac_geos_config_auto = "no" ; then
+      AC_MSG_ERROR([GEOS support explicitly enabled, but geos-config could not be found])
+    fi
+
   fi
 ])
 
diff -rupN --no-dereference gdal-3.2.2-fedora/m4/sfcgal.m4 gdal-3.2.2-fedora-new/m4/sfcgal.m4
--- gdal-3.2.2-fedora/m4/sfcgal.m4	2021-03-24 13:44:42.101428816 +0100
+++ gdal-3.2.2-fedora-new/m4/sfcgal.m4	2021-03-24 13:44:42.103428816 +0100
@@ -58,7 +58,9 @@ AC_DEFUN([SFCGAL_INIT],[
   elif test x"$with_sfcgal" = x"yes" -o x"$with_sfcgal" = x"" ; then
 
     AC_PATH_PROG(SFCGAL_CONFIG, sfcgal-config, no)
-    ac_sfcgal_config_auto=yes
+    if test x"$with_sfcgal" = x"" ; then
+      ac_sfcgal_config_auto=yes
+    fi
 
   else
 
@@ -140,7 +142,13 @@ AC_DEFUN([SFCGAL_INIT],[
 
 
       if test x"$HAVE_SFCGAL" = "xno"; then
-          SFCGAL_CFLAGS=""
+        if test $ac_sfcgal_config_auto = "yes" ; then
+          AC_MSG_WARN([SFCGAL was found on your system, but the library could not be linked. SFCGAL support disabled.])
+        else
+          AC_MSG_ERROR([SFCGAL library could not be linked])
+        fi
+
+        SFCGAL_CFLAGS=""
       fi
 
       CFLAGS="${ax_save_CFLAGS}"
@@ -149,5 +157,11 @@ AC_DEFUN([SFCGAL_INIT],[
 
     fi
 
+  else
+
+    if test $ac_sfcgal_config_auto = "no" ; then
+      AC_MSG_ERROR([SFCGAL support explicitly enabled, but sfcgal-config could not be found])
+    fi
+
   fi
 ])