[MacPorts] #56619: I ran "sudo port selfupdate" and now I cannot install any ports without an error

[MacPorts]

#56619: I ran "sudo port selfupdate" and now I cannot install any ports without an
error
---------------------------------+--------------------
  Reporter:  JulioDavidMartinez  |      Owner:  (none)
      Type:  defect              |     Status:  new
  Priority:  High                |  Milestone:
 Component:  base                |    Version:  2.5.2
Resolution:                      |   Keywords:
      Port:                      |
---------------------------------+--------------------
Description changed by ryandesign:

Old description:

> Here is the log:\\
>
> System headers do not appear to be installed. Most ports should build
> correctly, but if you experience problems due to a port depending on
> system headers, please file a ticket at https://trac.macports.org.\\
>
> Warning: You can install them as part of the Xcode Command Line Tools
> package by running `xcode-select --install'.\\
>
> --->  Computing dependencies for fontforgeError: Unable to determine
> location of a macOS SDK.\\
>
> Error: Unable to execute port: can't read "configure.sdkroot": Unable to
> determine location of a macOS SDK.\\
>

> It always asks me to install `xcode-select --install`, I have installed
> it like 50 times.
> This line is new since the update:\\
>
> Unable to execute port: can't read "configure.sdkroot":
>
> I have no idea what file this is nor where to locate it.
> How can I fix this?
> Please help.
> Im running Yosemite.
> I have XCode installed and the XCode Tools.
> I have been running MacPorts successfully for years on this station.
> Ever since the selfupdate today it broke.
> I cannot upgrade to High Sierra because we use an XSan system over fibre
> and the newer versions of OS X don't support our setup.
> I even tried uninstalling all my ports and deleting macports all together
> and then re-installing from scratch.
> Still gives me that error about the config file.

New description:

 Here is the log:

 {{{
 System headers do not appear to be installed. Most ports should build
 correctly, but if you experience problems due to a port depending on
 system headers, please file a ticket at https://trac.macports.org.
 Warning: You can install them as part of the Xcode Command Line Tools
 package by running `xcode-select --install'.
 --->  Computing dependencies for fontforgeError: Unable to determine
 location of a macOS SDK.
 Error: Unable to execute port: can't read "configure.sdkroot": Unable to
 determine location of a macOS SDK.
 }}}

 It always asks me to install `xcode-select --install`, I have installed it
 like 50 times.
 This line is new since the update:

 {{{
 Unable to execute port: can't read "configure.sdkroot":
 }}}

 I have no idea what file this is nor where to locate it.
 How can I fix this?
 Please help.
 Im running Yosemite.
 I have XCode installed and the XCode Tools.
 I have been running MacPorts successfully for years on this station.
 Ever since the selfupdate today it broke.
 I cannot upgrade to High Sierra because we use an XSan system over fibre
 and the newer versions of OS X don't support our setup.
 I even tried uninstalling all my ports and deleting macports all together
 and then re-installing from scratch.
 Still gives me that error about the config file.

--

-- 
Ticket URL: <https://trac.macports.org/ticket/56619#comment:4>
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