https://bugs.winehq.org/show_bug.cgi?id=46651
--- Comment #1 from Ken Thomases ken@codeweavers.com --- A workaround is to set the environment variable SDKROOT to the path to the SDK before the build, like so:
export SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk