--- a/gfx/thebes/moz.build
+++ b/gfx/thebes/moz.build
@@ -171,34 +171,39 @@ if CONFIG['INTEL_ARCHITECTURE']:
 SOURCES += [
     # Includes mac system header conflicting with point/size,
     # and includes glxXlibSurface.h which drags in Xrender.h
     'gfxASurface.cpp',
     # on X11, gfxDrawable.cpp includes X headers for an old workaround which
     # we could consider removing soon (affects Ubuntus older than 10.04 LTS)
     # which currently prevent it from joining UNIFIED_SOURCES.
     'gfxDrawable.cpp',
+    # gfxFontInfoLoader.cpp needs to set no_pgo for clang-cl
+    'gfxFontInfoLoader.cpp',
     # gfxFontUtils.cpp and gfxPlatform.cpp include mac system header conflicting with point/size
     'gfxFontUtils.cpp',
     'gfxPlatform.cpp',
     'gfxPrefs.cpp',
     'PrintTarget.cpp',
     'PrintTargetThebes.cpp',
 ]
 
+if CONFIG['CC_TYPE'] == 'clang-cl':
+    # clang-cl crashes trying to PGO this file (Bug 1479842)
+    SOURCES['gfxFontInfoLoader.cpp'].no_pgo = True
+
 UNIFIED_SOURCES += [
     'CJKCompatSVS.cpp',
     'gfxAlphaRecovery.cpp',
     'gfxBaseSharedMemorySurface.cpp',
     'gfxBlur.cpp',
     'gfxContext.cpp',
     'gfxFont.cpp',
     'gfxFontEntry.cpp',
     'gfxFontFeatures.cpp',
-    'gfxFontInfoLoader.cpp',
     'gfxFontMissingGlyphs.cpp',
     'gfxFontSrcPrincipal.cpp',
     'gfxFontSrcURI.cpp',
     'gfxGlyphExtents.cpp',
     'gfxGradientCache.cpp',
     'gfxGraphiteShaper.cpp',
     'gfxHarfBuzzShaper.cpp',
     'gfxImageSurface.cpp',