--- a/ChangeLog	Wed May 18 16:54:56 2016 +0100
+++ b/ChangeLog	Wed May 18 19:05:31 2016 +0100
@@ -1,3 +1,15 @@
+2016-05-17  Andrew John Hughes  <gnu.andrew@redhat.com>
+
+	PR2962: System default check doesn't match all
+	GNU/Linux systems
+	* NEWS: Updated.
+	* acinclude.m4:
+	(IT_CHECK_FOR_LCMS): Use a similar case statement
+	as in IT_SET_OS_DIRS to determine default based on OS.
+	(IT_CHECK_FOR_JPEG): Likewise.
+	(IT_CHECK_FOR_PNG): Likewise.
+	(IT_CHECK_FOR_GIF): Likewise.
+
 2016-05-17  Andrew John Hughes  <gnu.andrew@redhat.com>
 
 	PR2961: Latest security update broke bundled

--- a/NEWS	Wed May 18 16:54:56 2016 +0100
+++ b/NEWS	Wed May 18 19:05:31 2016 +0100
@@ -31,6 +31,7 @@
   - PR2954: ecj/override.patch is missing new @Overrides in RMIJRMPServerImpl.java
   - PR2957: Build bootstrap code (rt-class-files.stamp) using bootstrap flags (source/target 1.5)
   - PR2961: Latest security update broke bundled LCMS2 build
+  - PR2962: System default check doesn't match all GNU/Linux systems
 
 New in release 1.13.11 (2016-05-05):
 

--- a/acinclude.m4	Wed May 18 16:54:56 2016 +0100
+++ b/acinclude.m4	Wed May 18 19:05:31 2016 +0100
@@ -1566,10 +1566,15 @@
     ENABLE_SYSTEM_LCMS="${enableval}"
   ],
   [
-    if test x"${ENABLE_LCMS2}" = "xyes" -a x"${target_os}" = "xlinux-gnu" ; then
-      ENABLE_SYSTEM_LCMS="yes" ;
-    else
-      ENABLE_SYSTEM_LCMS="no" ;
+    if test x"${ENABLE_LCMS2}" = "xyes" ; then
+      case "${target_os}" in
+        *linux*)
+          ENABLE_SYSTEM_LCMS="yes"
+	  ;;
+	*)
+          ENABLE_SYSTEM_LCMS="no" ;
+	  ;;
+      esac
     fi;
   ])
   AC_MSG_RESULT(${ENABLE_SYSTEM_LCMS})
@@ -1596,11 +1601,14 @@
     ENABLE_SYSTEM_ZLIB="${enableval}"
   ],
   [
-    if test x"${target_os}" = "xlinux-gnu"; then
-      ENABLE_SYSTEM_ZLIB="yes" ;
-    else
-      ENABLE_SYSTEM_ZLIB="no" ;
-    fi
+    case "${target_os}" in
+      *linux*)
+        ENABLE_SYSTEM_ZLIB="yes"
+	;;
+      *)
+        ENABLE_SYSTEM_ZLIB="no" ;
+	;;
+    esac
   ])
   AC_MSG_RESULT(${ENABLE_SYSTEM_ZLIB})
   if test x"${ENABLE_SYSTEM_ZLIB}" = "xyes"; then
@@ -1627,11 +1635,14 @@
     ENABLE_SYSTEM_JPEG="${enableval}"
   ],
   [
-    if test x"${target_os}" = "xlinux-gnu"; then
-      ENABLE_SYSTEM_JPEG="yes" ;
-    else
-      ENABLE_SYSTEM_JPEG="no" ;
-    fi
+    case "${target_os}" in
+      *linux*)
+        ENABLE_SYSTEM_JPEG="yes"
+	;;
+      *)
+        ENABLE_SYSTEM_JPEG="no" ;
+	;;
+    esac
   ])
   AC_MSG_RESULT(${ENABLE_SYSTEM_JPEG})
   if test x"${ENABLE_SYSTEM_JPEG}" = "xyes"; then
@@ -1656,11 +1667,14 @@
     ENABLE_SYSTEM_PNG="${enableval}"
   ],
   [
-    if test x"${target_os}" = "xlinux-gnu"; then
-      ENABLE_SYSTEM_PNG="yes" ;
-    else
-      ENABLE_SYSTEM_PNG="no" ;
-    fi
+    case "${target_os}" in
+      *linux*)
+        ENABLE_SYSTEM_PNG="yes"
+	;;
+      *)
+        ENABLE_SYSTEM_PNG="no" ;
+	;;
+    esac
   ])
   AC_MSG_RESULT(${ENABLE_SYSTEM_PNG})
   if test x"${ENABLE_SYSTEM_PNG}" = "xyes"; then
@@ -1686,11 +1700,14 @@
     ENABLE_SYSTEM_GIF="${enableval}"
   ],
   [
-    if test x"${target_os}" = "xlinux-gnu"; then
-      ENABLE_SYSTEM_GIF="yes" ;
-    else
-      ENABLE_SYSTEM_GIF="no" ;
-    fi
+    case "${target_os}" in
+      *linux*)
+        ENABLE_SYSTEM_GIF="yes"
+	;;
+      *)
+        ENABLE_SYSTEM_GIF="no" ;
+	;;
+    esac
   ])
   AC_MSG_RESULT(${ENABLE_SYSTEM_GIF})
   if test x"${ENABLE_SYSTEM_GIF}" = "xyes"; then