--- a/mobile/android/geckoview/build.gradle
+++ b/mobile/android/geckoview/build.gradle
@@ -50,17 +50,18 @@ android {
 
         versionCode computeVersionCode()
         versionName "${mozconfig.substs.MOZ_APP_VERSION}-${mozconfig.substs.MOZ_UPDATE_CHANNEL}"
         consumerProguardFiles 'proguard-rules.txt'
 
         // TODO: ensure these fields always agree with mobile/android/geckoview/BuildConfig.java.in,
         // either by diffing the processed files or by generating the output from a single source.
         buildConfigField 'String', "GRE_MILESTONE", "\"${mozconfig.substs.GRE_MILESTONE}\""
-        buildConfigField 'String', "MOZ_APP_ABI", "\"${mozconfig.substs.TARGET_XPCOM_ABI}\"";
+        // This should really come from the included binaries, but that's not easy.
+        buildConfigField 'String', "MOZ_APP_ABI", mozconfig.substs['COMPILE_ENVIRONMENT'] ? "\"${ mozconfig.substs.TARGET_XPCOM_ABI}\"" : '"arm-eabi-gcc3"';
         buildConfigField 'String', "MOZ_APP_BASENAME", "\"${mozconfig.substs.MOZ_APP_BASENAME}\"";
 
         // For the benefit of future archaeologists:
         // GRE_BUILDID is exactly the same as MOZ_APP_BUILDID unless you're running
         // on XULRunner, which is never the case on Android.
         // 
         // Mimic Python: open(os.path.join(buildconfig.topobjdir, 'buildid.h')).readline().split()[2]
         buildConfigField 'String', "MOZ_APP_BUILDID", "\"${file("${topobjdir}/buildid.h").getText('utf-8').split()[2]}\"";