Meson has a common pattern of using 'if len(foo) == 0:' or
'if len(foo) != 0:', however, this is a common anti-pattern in python.
Instead tests for emptiness/non-emptiness should be done with a simple
'if foo:' or 'if not foo:'
Consider the following:
>>> import timeit
>>> timeit.timeit('if len([]) == 0: pass')
0.10730923599840025
>>> timeit.timeit('if not []: pass')
0.030033907998586074
>>> timeit.timeit('if len(['a', 'b', 'c', 'd']) == 0: pass')
0.1154778649979562
>>> timeit.timeit("if not ['a', 'b', 'c', 'd']: pass")
0.08259823200205574
>>> timeit.timeit('if len("") == 0: pass')
0.089759664999292
>>> timeit.timeit('if not "": pass')
0.02340641999762738
>>> timeit.timeit('if len("foo") == 0: pass')
0.08848102600313723
>>> timeit.timeit('if not "foo": pass')
0.04032287199879647
And for the one additional case of 'if len(foo.strip()) == 0', which can
be replaced with 'if not foo.isspace()'
>>> timeit.timeit('if len(" ".strip()) == 0: pass')
0.15294511600222904
>>> timeit.timeit('if " ".isspace(): pass')
0.09413968399894657
>>> timeit.timeit('if len(" abc".strip()) == 0: pass')
0.2023209120015963
>>> timeit.timeit('if " abc".isspace(): pass')
0.09571301700270851
In other words, it's always a win to not use len(), when you don't
actually want to check the length.
The MSVC static library tool, lib.exe, does not understand the same set
of arguments as the linker. Avoid a warning by not adding /DEBUG or /PDB
to the command line when invoking lib.exe
Now as long as you have a C compiler available in the project, it will
be used to compile assembly even if the target contains a C++ compiler
and even if the target contains only assembly and C++ sources.
Earlier, the order in which sources appeared in a target would decide
which compiler would be used.
However, if the project only provides a C++ compiler, that will be
used for compiling assembly sources.
If this breaks your use-case, please tell us.
Includes a test that ensures that all of the above is adhered to.
These compilers are available in MinGW and can be built on macOS.
More interestingly, `gcc` is a wrapper around `clang` on macOS, so we
will detect the compiler type incorrectly on macOS without this.
It's only useful to use those when you have to override include dirs
or library paths by appending them from various sources according to
the priority order, or if the compiler args need to be converted from
Unix/GCC-style to native (MSVC, for instance) style.
Sanity checks match neither of these.
Closes https://github.com/mesonbuild/meson/issues/1351
The purpose of this class is to make it possible to sanely generate
compiler command-lines by ensuring that new arguments appended or added
to a list of arguments properly override previous arguments.
For instance:
>>> a = CompilerArgs(['-Lfoo', '-DBAR'])
>>> a += ['-Lgah', '-DTAZ']
>>> print(a)
['-Lgah', '-Lfoo', '-DBAR', '-DTAZ']
Arguments will be de-duped if it is safe to do so. Currently, this is
only done for -I and -L arguments (previous occurances are removed when
a new one is added) and arguments that once added cannot be overriden
such as -pipe are removed completely.
Use a single check for both cases when we have includes and when we
don't. This way we ensure three things:
1. Built-in checks are 100% reliable with clang and on macOS since clang
implements __has_builtin
2. When the #include is present, this ensures that __builtin_func is not
checked for (because of MSYS, and because it is faster)
3. We fallback to checking __builtin_func when all else fails
prefix might define _GNU_SOURCE, which *must* be defined before your
first include of limits.h, so we must define it first.
There's not really any downsides to including limits.h after the
prefix.
Our "43 has function" test should also work with clang and icc on Linux,
so enable them. Also detect builtins with __has_builtin if available,
which is much faster on clang.
There is a feature request for the same with GCC too:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66970
If it's available, it's much much faster than doing #include
+ preprocess. Speeds up has_header checks by about 40% for me.
Currently, only Clang supports this
These two are also C-like sources, so don't ignore them in
backends/ninjabackend.py:generate_target() when we call
is_source() on the list of generated sources for that target.
Closes#1318
And fix the list of supported file suffixes, and use .f90 for all
fortran tests since ifort, the Intel Fortran compiler ignores files
ending with .f95, .f03, and .f08
Compiler versions 15.0 and later actually ignore invalid values for the
-std= option unless `-diag-error 10159` is passed, so we need to put
that in the unit test.
I have tested this with versions 14.0.3, 15.0.6, 16.0.4, and 17.0.1.
Would be great if someone could test with 13.x.y
Added IntelCompiler, IntelCCompiler and IntelCCompiler.
environments.py has been changed to detect icc and icpc.
ninjabackend changed for proper pch generation.
ICC 17.0.0 does not support C++13 (that's why default arguments tests fails).
Test 25 object extraction fails due to some unescaped whitespaces.
Some test with vala fail because of successful build, although they
should fail, as warning do not exit with failure.
Dylan Baker
Nirbheek Chauhan
Jussi Pakkanen
Jon Turney
Peter Harris
Matthias Klumpp
Haakon Sporsheim
Rodrigo Lourenço
Mike Sinkovsky
Philipp Geier
Igor Gnatenko