[build2] build2 not Compiling on Raspberry Pi ARMv7 Architecture

[Boris Kolpackov]

Markus Pawellek <markus.pawellek at mailbox.org> writes:

> I do not know very much about the actual implementation of build2
> but with respect to the second alternative, even if it would suffer
> from a poor performance, it may not be a dramatic problem, because
> in my opinion on a Raspberry Pi one is typically dealing with small
> code projects.

One thing to keep in mind is that build2 builds itself and it's not
exactly small.

In fact, the reason we have those checks is that we don't actually
know how bad is the performance hit. If it's not much, we could just
remove them.

So in this light it would have actually been useful to try to build
build2 with both 32-bit Raspbian (with these checks disabled) and
then with 64-bit and compare how long it takes.

The way I would do it is get the build2-toolchain package (skipping
the install script) and then do a timed local build:

$ cd build2-toolchain
$ time ./build.sh --local --make make -j 4 --install-dir /tmp/install g++

For the 32-bit build I would just edit build2/libbuild2/target.hxx and
add `#define LIBBUILD2_ATOMIC_NON_LOCK_FREE` on top to disable the checks.

If you do get to run this test, I would be interested to hear the result.