JDK-8199608 introduced a build race on macosx. The declaration:

$(BUILD_LIBFONTMANAGER): $(BUILD_LIBAWT_LWAWT)

does not work because the SetupNativeCompilation call for BUILD_LIBAWT_LWAWT is positioned further down in the file.

I propose this simple patch:

diff -r 149dc554808c make/lib/Awt2dLibraries.gmk
--- a/make/lib/Awt2dLibraries.gmk
+++ b/make/lib/Awt2dLibraries.gmk
@@ -667,7 +667,7 @@
 endif
 
 ifeq ($(OPENJDK_TARGET_OS), macosx)
- $(BUILD_LIBFONTMANAGER): $(BUILD_LIBAWT_LWAWT)
+ $(BUILD_LIBFONTMANAGER): $(call FindLib, java.desktop, awt_lwawt)
 endif
 
 ifeq ($(FREETYPE_TO_USE), bundled)