The `-ffile-prefix-map` compiler option implicitly enables
`-fprofile-prefix-map` in GCC or `-fcoverage-prefix-map` in Clang, which
can cause issues with coverage builds.
This change ensures that only the options necessary for build
reproducibility are applied.
Rather than setting this per package, set it globally, as this is always
what we want. Without doing this, later commit will have to add the same
doc + change to more packages.
On some systems, capnp would be installed into `lib64`, I
assume due to the use of GNUInstallDirs, however all other libs we build
in depends, go into lib/. Rather than adding lib64/ to the pkg-config
and link flags, I opted for always installing into lib/.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
From `configure --help`:
--with-external-capnp use the system capnp binary (or the one specified
with $CAPNP) instead of compiling a new one (useful
for cross-compiling)
The non-native capnp was trying to fetch the wrong file.
Without this, "make -C depends MULTIPROCESS=1 download" is broken.
Presumably it breaks with the download target because the dependency graph is
flattened. It manages to work if native_capnp is encountered first because it
will then be found in the cache.
