--- a/build/macosx/local-mozconfig.common
+++ b/build/macosx/local-mozconfig.common
@@ -22,16 +22,19 @@ fi
 
 if [ -d $TOOLTOOL_DIR/MacOSX10.10.sdk ]; then
     export CROSS_SYSROOT=$TOOLTOOL_DIR/MacOSX10.10.sdk
     CROSS_PRIVATE_FRAMEWORKS=$CROSS_SYSROOT/System/Library/PrivateFrameworks
     FLAGS="-isysroot $CROSS_SYSROOT"
     ldflags="-Wl,-syslibroot,$CROSS_SYSROOT "
     export BINDGEN_CFLAGS="$FLAGS"
     ac_add_options --with-macos-private-frameworks=$CROSS_PRIVATE_FRAMEWORKS
+    # Since we are manually providing an SDK, don't check for xcode being installed.
+    # See https://bugzilla.mozilla.org/show_bug.cgi?id=1366564
+    ac_add_options --disable-xcode-checks
 else
     FLAGS=""
 fi
 
 if [ -d $TOOLTOOL_DIR ]; then
     export CC="$TOOLTOOL_DIR/clang/bin/clang $FLAGS"
     export CXX="$TOOLTOOL_DIR/clang/bin/clang++ $FLAGS"
     export CPP="$TOOLTOOL_DIR/clang/bin/clang $FLAGS -E"