C like compilers only off `-DNDEBUG` to disable asserts. This is not a
universal paradigm however. Rust, for example has an argument that takes
a boolean. To better represent this, we allow passing a `disable`
boolean. `disable` was chosen rather than `enable` because it allowed
all existing logic to be left in place
This option was introduced with GCC 8.1.0 as in the original commit, but the
value wasn't right initially and was volatile during the 8 series.
To avoid this, this commit moves the warning to 9.1.0 (the next version we
generally care about), since we don't want to get too deep into the weeds of
point releases, and a warning not being used yet in some particular version of
GCC isn't a big deal.
Eventually we would probably be better served (to avoid unnecessary
copies) to use the ImmutableListProtocol here, but for the moment this
is effective, it's also what we do in every other case.
We assume /utf-8 for all C builds unless /source-charset or
/execution-charset is specified, but then this will cause trouble for
Visual Studio 2013 or earler since the /utf-8 flag is only supported
since Visual Studio 2015. Specifically, if we try to check whether
compiler flags are supported, those checks will fail since /utf-8 is
never supported on these older Visual Studio versions.
Drop /utf-8 from get_always_args() if we are using Visual Studio 2013
or earlier.
Profiling showed that we were spending 25s inside os.path.realpath()
on Windows while generating compile lines for build.ninja, inside
NinjaBackend.generate()
The real path for these will not (should not) change during a single
meson invocation, so cache all these.
Brings build.ninja generation from 73s to 47s on my machine.
Which adds the `use-set-for-membership` check. It's generally faster in
python to use a set with the `in` keyword, because it's a hash check
instead of a linear walk, this is especially true with strings, where
it's actually O(n^2), one loop over the container, and an inner loop of
the strings (as string comparison works by checking that `a[n] == b[n]`,
in a loop).
Also, I'm tired of complaining about this in reviews, let the tools do
it for me :)
Adds a new maximum warning level that is roughly equivalent to "all warnings".
This adds a way to use `/Wall` with MSVC (without the previous broken warning),
`-Weverything` with clang, and almost all general warnings in GCC with
strictness roughly equivalent to clang's `-Weverything`.
The GCC case must be implemented by meson since GCC doesn't provide a similar
option. To avoid maintenance headaches for meson, this warning level is
defined objectively: all warnings are included except those that require
specific values or are specific to particular language revisions. This warning
level is mainly intended for new code, and it is expected (nearly guaranteed)
that projects will need to add some suppressions to build cleanly with it.
More commonly, it's just a handy way to occasionally take a look at what
warnings are present with some compiler, in case anything interesting shows up
you might want to enable in general.
Since the warnings enabled at this level are inherently unstable with respect
to compiler versions, it is intended for use by developers and not to be set as
the default.
ccache was used in all command lines but disabled using CCACHE_DISABLE
in Compiler.compile() method. Wrapping invokations still has a cost,
especially on Windows.
With sccache things are even worse because CCACHE_DISABLE was not
respected at all, making configure *extremely* slow on Windows when
sccache is installed.
https://github.com/mesonbuild/meson/pull/9287 changed the `optimization=0`
to pass `-O0` to the compiler. This change is reasonable by itself
but unfortunately, it breaks `buildtype=plain`, which promises
that “no extra build flags are used”.
`buildtype=plain` is important for distros like NixOS,
which manage compiler flags for optimization and hardening
themselves.
Let’s introduce a new optimization level that does nothing
and set it as the default for `buildtype=plain`.
We need to support cases where the library might be called "foo.so" and
therefore we check for exact matches too. But this also allows
`cc.find_library('libfoo')` to find libfoo.so, which is strange and
won't work in many cases. Emit a warning when this happens.
Fixes#10838
We *mostly* just need to do the same thing. Plug in one utility method
to make sanity_check_impl find the right compile args, and plug in
DEVNULL to the test run. It's that simple.
This solves a few inconsistencies. The main one is that fortran never
logged the sanity checks to the Meson debug log, making it hard to
debug.
There's also some interesting quirks we built up in the dedicated
fortran handling. For example:
- in commit 5b109c9ad2 we added cwd to
building the fortran executable, with a wordy comment about how the
compiler has defects. But the clike base has always done that on
general principle anyway, so we would never have had that bug in the
first place.
- in commit d6be7822a0 we added special
deletion of an old "bad existing exe file" just for fortran. Looking
at the PR discussion for this odd requirement, it turns out that the
real problem is mixing WSL and native Windows without deleting the
build directory. This is apparently fortran specific simply because
"contemporary Windows 10 Fortran users" switch between the two?
The actual problem is that this never used .exe as the output name, so
Windows thinks you want to run something other than the thing you
asked to run, because it's not even a Window executable. But... the
common clike handling could have fixed that without needing special
cases.
Specifically, this is a combination of the following:
- Revert "visualstudio.py: Apply /utf-8 only on clang or VS2015+"
This reverts commit 6e7c3efa79.
- Revert "Visual Studio: Only use /utf-8 on VS2015 or later or clang-cl"
This reverts commit 8ed151bbd7.
The changes were broken and untested, although this is because of a lack
of general CI testing for all languages on Windows. At least, this broke
the use of ifort, and possibly more.
The changes are fundamentally a bit "exciting", as they step out of the
hierarchy of compiler definitions and apply arguments almost willy-nilly.
And apparently it's leaky all over the place. I don't understand all of
what is going on with it, but it plainly failed to achieve its desired
goal and needs to be rolled back ASAP.
In PR 10263, we didn't account for that we may have initialize the Visual
Studio-like compiler two times, once for a C compiler and once for the
C++ compiler, so we end up with Meson breaking on Visual Studio 2013
or earlier, such as when building GLib.
Fix this by setting up the always_args member of
the VisualStudioLikeCompiler instance during __init__() as needed, so that
we avoid falling into modifying shared objects.
This option is only valid for C++ and ObjC++, but the kwarg is useful
for mixed language targets. Asking for inlines as well, when the
compiler driver is trying to build the C components of a target, results
in gcc emitting:
```
cc1: warning: command-line option ‘-fvisibility-inlines-hidden’ is valid for C++/ObjC++ but not for C
```
Squelch this warning by filtering it out on Meson's side of things.
[why]
Support for the relatively new mold linker is missing. If someone wants
to use mold as linker `LDFLAGS="-B/path/to/mold"` has to be added instead
of the usual `CC_LD=mold meson ...` or `CXX_LD=mold meson ...`.
[how]
Allow `mold' as linker for clang and newer GCC versions (that versions
that have support).
The error message can be a bit off, because it is generic for all GNU
like compilers, but I guess that is ok. (i.e. 'mold' is not listed as
possible linker, even if it would be possible for the given compiler.)
[note]
GCC Version 12.0.1 is not sufficient to say `mold` is supported. The
expected release with support will be 12.1.0.
On the other hand people that use the un-released 12.0.1 will probably
have built it from trunk. Allowing 12.0.1 is helping bleeding edge
developers to use mold in Meson already now.
Fixes: #9072
Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>
The compiler flag only exists on Visual Studio 2015 or later, or clang-cl,
and using this always can interfere with compiler feature detection when
this flag is not supported.
So, remove '/utf-8' from always_args if we are on Visual Studio 2013 or
earlier.
This has been broken ever since the original implementation. Due to a
typo, the optimization flag used a zero instead of an uppercase "o",
which the compiler then breaks on during argument parsing because it is
an invalid argument.
Fixes#10267
When something goes wrong with running the compiler in
_symbols_have_underscore_prefix_searchbin, print stderr instead,
as it actually contains helpful output while stdout is usually empty
in this case.