On Dec 28, 2020, at 06:12, Christoph Kukulies wrote:
> I’m trying to compile a package „blackmagic“ (a microcontroller gdb debugging
> and flashing program addendum to gdb).
>
> It has some issues like missing packages (libftdi1 - I was able to add that
> via macports)
>
> Now I want to add some condional in the Makefile like this:
>
> ifdef macOS
>
> CFLAGS += -I/opt/local/include
>
> endif
>
> Only, macOS isn’t just the variable that works. Does macOS supply any
> built-in variable for building that if block?
You should not need to do this.
Most build systems should accept additional flags on the command line. For
example, autotools-based build systems usually accept something like:
CPPFLAGS="-I/opt/local/include" LDFLAGS="-L/opt/local/lib" ./configure
If blackmagic doesn't do it that way, consult their documentation to find out
how they do it. In the unlikely event that their build system does not support
user-supplied flags, file that as a bug in their bug tracker. You may then need
to resort to modifying their Makefile or other build files manually, and if so,
since the modification is just for you, you don't need to make it conditional
on macOS or anything else; just make the change unconditionally.
If you were thinking of proposing a change to the developers of blackmagic
where they automatically add /opt/local paths on macOS, don't. That would annoy
users trying to build it with Homebrew, Fink, or manually, and it would even
annoy MacPorts users trying to build with MacPorts in a prefix other than
/opt/local.
