[MacPorts] #55577: getting rid of unforeseen -I${prefix}/include option adding and its potential side-effects

[MacPorts]

#55577: getting rid of unforeseen -I${prefix}/include option adding and its
potential side-effects
--------------------------+-----------------
  Reporter:  RJVB         |      Owner:
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:
      Port:  pcre, glib2  |
--------------------------+-----------------

Comment (by ryandesign):

 Replying to [comment:5 RJVB]:
 > This fixes the port for any future change in port:pcre:
 >
 > {{{
 > if {[variant_isset pcre]} {
 >     depends_build-append \
 >                     port:pkgconfig
 >     if {[file exists ${prefix}/bin/pkg-config]} {
 >         # fetch the flags required for building with the local pcre2
 install
 >         set CFLAGS  "${CFLAGS} [exec ${prefix}/bin/pkg-config --cflags
 libpcre2-8]"
 >     }
 > }
 > }}}

 This will not work if pkgconfig is not installed at the time the user
 requests to install git. In general ports should not alter their behavior
 dependent on whether other MacPorts-installed files are already present.
 If we were going to add such code, you would do so in a pre-build block,
 so that it is guaranteed that pkgconfig is installed by then. The way that
 the git port sets build.args would also have to be altered, to do so at
 pre-build time. But I wouldn't make these changes to the git port unless
 we change the pcre port in the way that you've requested.

--
Ticket URL: <https://trac.macports.org/ticket/55577#comment:7>
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