diff --git a/MozillaFirefox.changes b/MozillaFirefox.changes
index 631cde0..fafda00 100644
--- a/MozillaFirefox.changes
+++ b/MozillaFirefox.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Fri Feb 26 16:22:52 UTC 2016 - astieger@suse.com
+
+- fix build problems on i586, caused by too large unified compile
+  units - adding mozila-reduce-files-per-UnifiedBindings.patch
+
 -------------------------------------------------------------------
 Thu Feb 11 07:51:34 UTC 2016 - wr@rosenauer.org
 
diff --git a/MozillaFirefox.spec b/MozillaFirefox.spec
index d8263f9..71a7926 100644
--- a/MozillaFirefox.spec
+++ b/MozillaFirefox.spec
@@ -159,6 +159,7 @@ Patch7:         mozilla-repo.patch
 Patch8:         mozilla-openaes-decl.patch
 Patch10:        mozilla-no-stdcxx-check.patch
 Patch11:        mozilla-libproxy.patch
+Patch12:        mozilla-reduce-files-per-UnifiedBindings.patch
 # Firefox/browser
 Patch101:       firefox-kde.patch
 Patch102:       firefox-no-default-ualocale.patch
@@ -268,6 +269,7 @@ cd $RPM_BUILD_DIR/mozilla
 %patch8 -p1
 %patch10 -p1
 %patch11 -p1
+%patch12 -p1
 # Firefox
 %patch101 -p1
 %patch102 -p1
diff --git a/mozilla-reduce-files-per-UnifiedBindings.patch b/mozilla-reduce-files-per-UnifiedBindings.patch
new file mode 100644
index 0000000..391fa8e
--- /dev/null
+++ b/mozilla-reduce-files-per-UnifiedBindings.patch
@@ -0,0 +1,28 @@
+From: Andreas Stieger <astieger@suse.com>
+Date: Fri, 26 Feb 2016 16:20:09 +0000
+Subject: For UnifiedBindings*.cpp files, reduce number of files per unified file
+Upstream: no
+
+home/abuild/rpmbuild/BUILD/obj/dom/bindings/UnifiedBindings16.cpp
+[ 1589s] UnifiedBindings17.o
+[ 1612s] [ 1567.621989] Out of memory: Kill process 19849 (cc1plus) score 170 or sacrifice child
+[ 1612s] [ 1567.625099] Killed process 19849 (cc1plus) total-vm:905704kB, anon-rss:102500kB, file-rss:156kB
+[ 1616s] {standard input}: Assembler messages:
+[ 1616s] {standard input}:316015: Warning: end of file not at end of a line; newline inserted
+[ 1635s] {standard input}: Error: open CFI at the end of file; missing .cfi_endproc directive
+[ 1636s] c++: internal compiler error: Killed (program cc1plus)
+[ 1636s] Please submit a full bug report,
+
+Index: mozilla/python/mozbuild/mozbuild/backend/common.py
+===================================================================
+--- mozilla.orig/python/mozbuild/mozbuild/backend/common.py	2016-02-26 17:19:30.331667693 +0100
++++ mozilla/python/mozbuild/mozbuild/backend/common.py	2016-02-26 17:19:39.792569676 +0100
+@@ -333,7 +333,7 @@ class CommonBackend(BuildBackend):
+         unified_source_mapping = list(group_unified_files(webidls.all_regular_cpp_basenames(),
+                                                           unified_prefix='UnifiedBindings',
+                                                           unified_suffix='cpp',
+-                                                          files_per_unified_file=32))
++                                                          files_per_unified_file=16))
+         self._write_unified_files(unified_source_mapping, bindings_dir,
+                                   poison_windows_h=True)
+         self._handle_webidl_build(bindings_dir, unified_source_mapping,