[MacPorts] #61541: gd2 2.3.0_0 +x11.darwin on Intel/BigSur: clang: error: invalid version number in 'MACOSX_DEPLOYMENT_TARGET=11.0'

[MacPorts]

#61541: gd2 2.3.0_0 +x11.darwin on Intel/BigSur: clang: error: invalid version
number in 'MACOSX_DEPLOYMENT_TARGET=11.0'
-----------------------+--------------------
 Reporter:  shibukawa  |      Owner:  (none)
     Type:  defect     |     Status:  new
 Priority:  Normal     |  Milestone:
Component:  ports      |    Version:  2.6.4
 Keywords:             |       Port:
-----------------------+--------------------
 When I reinstall gd2 on my BigSur installed mac, I got error:

 {{{
 % sudo port install gd2
 Warning: The macOS 11.0 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'.
 --->  Computing dependencies for gd2
 --->  Fetching archive for gd2
 --->  Attempting to fetch gd2-2.3.0_0+x11.darwin_20.x86_64.tbz2 from
 https://kmq.jp.packages.macports.org/gd2
 --->  Attempting to fetch gd2-2.3.0_0+x11.darwin_20.x86_64.tbz2 from
 http://jog.id.packages.macports.org/macports/packages/gd2
 --->  Attempting to fetch gd2-2.3.0_0+x11.darwin_20.x86_64.tbz2 from
 https://packages.macports.org/gd2
 --->  Configuring gd2
 Error: Failed to configure gd2, consult
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_graphics_gd2/gd2/work/libgd-2.3.0/config.log
 Error: Failed to configure gd2: configure failure: command execution
 failed
 Error: See
 /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_graphics_gd2/gd2/main.log
 for details.
 Error: Follow https://guide.macports.org/#project.tickets to report a bug.
 Error: Processing of port gd2 failed
 }}}

 The log contains the following error:

 {{{
 clang: error: invalid version number in 'MACOSX_DEPLOYMENT_TARGET=11.0'
 }}}

 On my console, I got warning about xcode-select --install, but this
 command dumps the following message and I could install other ports like
 nodejs14 (it was built from source), so this is not the cause I think.

 {{{
 % sudo xcode-select --install
 xcode-select: error: command line tools are already installed, use
 "Software Update" to install updates
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/61541>
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