diff --git a/gfx/cairo/libpixman/src/moz.build b/gfx/cairo/libpixman/src/moz.build
--- a/gfx/cairo/libpixman/src/moz.build
+++ b/gfx/cairo/libpixman/src/moz.build
@@ -162,8 +162,27 @@ if CONFIG['_MSC_VER'] and not CONFIG['CL
         '-wd4133', # 'function' : incompatible types
         '-wd4146', # unary minus operator applied to unsigned type
         '-wd4311', # 'variable' : pointer truncation from 'type' to 'type'
     ]
 
 # See bug 386897.
 if CONFIG['OS_TARGET'] == 'Android' and CONFIG['MOZ_OPTIMIZE']:
     CFLAGS += ['-O2']
+
+if CONFIG['_MSC_VER']:
+    if '-DTT_MEMUTIL' in CONFIG['MOZ_OPTIMIZE_FLAGS']:
+        SOURCES['pixman-implementation.c'].flags += [
+            '-GL-',
+            '-openmp',
+        ]
+        SOURCES['pixman-general.c'].flags += [
+            '-GL-',
+            '-openmp',
+        ]
+        SOURCES['pixman-trap.c'].flags += [
+            '-GL-',
+            '-openmp',
+        ]
+        SOURCES['pixman-sse2.c'].flags += [
+            '-GL-',
+            '-openmp',
+        ]
