[MacPorts] #59503: gmp: The macOS 10.14 SDK does not appear to be installed (but it is)

[MacPorts]

#59503: gmp: The macOS 10.14 SDK does not appear to be installed (but it is)
------------------------+---------------------------------
 Reporter:  ryandesign  |      Owner:  MarcusCalhoun-Lopez
     Type:  defect      |     Status:  assigned
 Priority:  Normal      |  Milestone:
Component:  ports       |    Version:  2.6.2
 Keywords:  mojave      |       Port:  gmp
------------------------+---------------------------------
 While upgrading infrastructure ports on the Mojave buildbot worker, I
 noticed this warning:

 {{{
 Warning: The macOS 10.14 SDK does not appear to be installed. Ports may
 not build correctly.
 Warning: You can install it as part of the Xcode Command Line Tools
 package by running `xcode-select --install'.
 --->  Fetching distfiles for gmp
 --->  Attempting to fetch gmp-6.1.2.tar.bz2 from
 https://distfiles.macports.org/gmp
 --->  Verifying checksums for gmp
 --->  Extracting gmp
 --->  Applying patches to gmp
 --->  Configuring gmp
 --->  Building gmp
 --->  Staging gmp into destroot
 --->  Installing gmp @6.1.2_3
 --->  Cleaning gmp
 Warning: The macOS 10.14 SDK does not appear to be installed. Ports may
 not build correctly.
 Warning: You can install it as part of the Xcode Command Line Tools
 package by running `xcode-select --install'.
 --->  Deactivating gmp @6.1.2_1
 --->  Cleaning gmp
 --->  Activating gmp @6.1.2_3
 --->  Cleaning gmp
 }}}

 This machine has Xcode 10.3 and the Xcode 10.3 version of the command line
 tools installed, so the macOS 10.14 SDK does exist in both of the usual
 places:

 {{{
 $ ls -ld
 {/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer,/Library/Developer/CommandLineTools}/SDKs/MacOSX10.14.sdk
 lrwxr-xr-x  1 root  wheel  10 Sep 20 22:36
 /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk
 -> MacOSX.sdk
 lrwxr-xr-x  1 root  wheel  10 Oct 23 18:36
 /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk -> MacOSX.sdk
 }}}

 This warning only appeared when upgrading the gmp port, not when upgrading
 other ports.

 I think this problem may be happening because the gmp port clears
 `configure.sdkroot`.

-- 
Ticket URL: <https://trac.macports.org/ticket/59503>
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