[MacPorts] #71162: xar @1.8.0.501_0: error: implicit declaration of function 'xar_prop_get_expect_notnull' is invalid in C99 [-Werror, -Wimplicit-function-declaration]

[MacPorts]

#71162: xar @1.8.0.501_0: error: implicit declaration of function
'xar_prop_get_expect_notnull' is invalid in C99 [-Werror,-Wimplicit-
function-declaration]
-------------------------+------------------------------
  Reporter:  ryandesign  |      Owner:  Schamschula
      Type:  defect      |     Status:  assigned
  Priority:  High        |  Milestone:
 Component:  ports       |    Version:  2.10.2
Resolution:              |   Keywords:  bigsur, monterey
      Port:  xar         |
-------------------------+------------------------------

Comment (by ryandesign):

 Replying to [comment:13 lukaso]:
 > Simply that `xar` won't build (I have to build everything from source
 for the GIMP build because I target older SDKs).

 Ok, that probably explains it. I see in your log that you are on macOS 15
 but using the macOS 11 SDK and deployment target. As we know from this
 ticket, our xar build inadvertently uses the xar.h header from the SDK
 instead of the one from the new version of xar. This works ok with the
 current macOS SDK but not with older SDKs that have the older xar.h
 header. The port should be fixed so that it uses the xar.h header from the
 port, not the SDK, by reinstating the fix for #64842. However, per my
 [attachment:xar.diff work in progress], that hasn't been sufficient to
 allow building again; I have not investigated further.

 The quickest fix for your situation is to [wiki:howto/InstallingOlderPort
 use version 498] instead of 501.

-- 
Ticket URL: <https://trac.macports.org/ticket/71162#comment:16>
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