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dev-util/meson: backport patch to stop hiding vala compiler warnings
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This is especially bad because it makes these packages disappear
entirely from QA checks for, say, Modern C. Although it's only a matter
of adding more warnings, and doesn't really affect the resulting
packages, we need this live in order to do proper QA.

Bug: https://bugs.gentoo.org/870412
Signed-off-by: Eli Schwartz <eschwartz93@gmail.com>
Closes: #34141
Signed-off-by: Sam James <sam@gentoo.org>
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eli-schwartz authored and thesamesam committed Dec 6, 2023
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250 changes: 250 additions & 0 deletions dev-util/meson/files/0001-ninja-backend-don-t-hide-all-compiler-warnings-for-t.patch
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From 5f659af870011e74299d1455a65c2cd5f5ace51f Mon Sep 17 00:00:00 2001
From: Eli Schwartz <eschwartz93@gmail.com>
Date: Tue, 5 Dec 2023 14:26:54 -0500
Subject: [PATCH] ninja backend: don't hide all compiler warnings for
transpiled languages

This was originally added for vala only, with the rationale that vala
generates bad code that has warnings. Unfortunately, the rationale was
fatally flawed. The compiler warns about a number of things, which the
user can control depending on their code (or their code generator's
code), but some of those things are absolutely critical to warn about.

In particular, GCC 14 and clang 17 are updating their defaults to warn
-- and error by default for -- invalid C code that breaks the standard,
but has been silently accepted for over 20 years "because lots of people
do it". The code in question is UB, and compilers will generate faulty
machine code that behaves erroneously and probably has a mass of CVEs
waiting to happen.

Compiler warnings are NOT safe to just... universally turn off. Compiler
warnings could be either:

- coding style lints

- threatening statements that the code is factually and behaviorally wrong

There is no magic bullet to ignore the former while respecting the
latter. And the very last thing we should ever do is pass `-w`, since
that causes ALL warnings to be disabled, even the manually added
`-Werror=XXX`.

If vala generated code creates warnings, then the vala compiler can
decrease the log level by generating better code, or by adding warning
suppression pragmas for *specific* issues, such as unused functions.
---
mesonbuild/backend/backends.py | 13 ++-----
mesonbuild/backend/ninjabackend.py | 19 ++++------
.../failing build/1 vala c werror/meson.build | 10 -----
.../failing build/1 vala c werror/prog.vala | 7 ----
.../1 vala c werror/unused-var.c | 8 ----
test cases/vala/5 target glib/meson.build | 4 --
unittests/linuxliketests.py | 37 -------------------
7 files changed, 11 insertions(+), 87 deletions(-)
delete mode 100644 test cases/failing build/1 vala c werror/meson.build
delete mode 100644 test cases/failing build/1 vala c werror/prog.vala
delete mode 100644 test cases/failing build/1 vala c werror/unused-var.c

diff --git a/mesonbuild/backend/backends.py b/mesonbuild/backend/backends.py
index 2c24e4c31..639e07b2a 100644
--- a/mesonbuild/backend/backends.py
+++ b/mesonbuild/backend/backends.py
@@ -986,7 +986,7 @@ class Backend:
return compiler.get_no_stdinc_args()
return []

- def generate_basic_compiler_args(self, target: build.BuildTarget, compiler: 'Compiler', no_warn_args: bool = False) -> 'CompilerArgs':
+ def generate_basic_compiler_args(self, target: build.BuildTarget, compiler: 'Compiler') -> 'CompilerArgs':
# Create an empty commands list, and start adding arguments from
# various sources in the order in which they must override each other
# starting from hard-coded defaults followed by build options and so on.
@@ -999,17 +999,12 @@ class Backend:
commands += self.get_no_stdlib_args(target, compiler)
# Add things like /NOLOGO or -pipe; usually can't be overridden
commands += compiler.get_always_args()
- # Only add warning-flags by default if the buildtype enables it, and if
- # we weren't explicitly asked to not emit warnings (for Vala, f.ex)
- if no_warn_args:
- commands += compiler.get_no_warn_args()
- else:
- # warning_level is a string, but mypy can't determine that
- commands += compiler.get_warn_args(T.cast('str', target.get_option(OptionKey('warning_level'))))
+ # warning_level is a string, but mypy can't determine that
+ commands += compiler.get_warn_args(T.cast('str', target.get_option(OptionKey('warning_level'))))
# Add -Werror if werror=true is set in the build options set on the
# command-line or default_options inside project(). This only sets the
# action to be done for warnings if/when they are emitted, so it's ok
- # to set it after get_no_warn_args() or get_warn_args().
+ # to set it after or get_warn_args().
if target.get_option(OptionKey('werror')):
commands += compiler.get_werror_args()
# Add compile args for c_* or cpp_* build options set on the
diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 049ae253f..cdb747d73 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -1939,7 +1939,7 @@ class NinjaBackend(backends.Backend):
if cratetype in {'bin', 'dylib'}:
args.extend(rustc.get_linker_always_args())

- args += self.generate_basic_compiler_args(target, rustc, False)
+ args += self.generate_basic_compiler_args(target, rustc)
# Rustc replaces - with _. spaces or dots are not allowed, so we replace them with underscores
args += ['--crate-name', target.name.replace('-', '_').replace(' ', '_').replace('.', '_')]
depfile = os.path.join(target.subdir, target.name + '.d')
@@ -2804,10 +2804,9 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
bargs = []
return (sargs, bargs)

- def _generate_single_compile(self, target: build.BuildTarget, compiler: 'Compiler',
- is_generated: bool = False) -> 'CompilerArgs':
+ def _generate_single_compile(self, target: build.BuildTarget, compiler: Compiler) -> CompilerArgs:
commands = self._generate_single_compile_base_args(target, compiler)
- commands += self._generate_single_compile_target_args(target, compiler, is_generated)
+ commands += self._generate_single_compile_target_args(target, compiler)
return commands

def _generate_single_compile_base_args(self, target: build.BuildTarget, compiler: 'Compiler') -> 'CompilerArgs':
@@ -2825,14 +2824,10 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
return commands

@lru_cache(maxsize=None)
- def _generate_single_compile_target_args(self, target: build.BuildTarget, compiler: 'Compiler',
- is_generated: bool = False) -> 'ImmutableListProtocol[str]':
- # The code generated by valac is usually crap and has tons of unused
- # variables and such, so disable warnings for Vala C sources.
- no_warn_args = is_generated == 'vala'
+ def _generate_single_compile_target_args(self, target: build.BuildTarget, compiler: Compiler) -> ImmutableListProtocol[str]:
# Add compiler args and include paths from several sources; defaults,
# build options, external dependencies, etc.
- commands = self.generate_basic_compiler_args(target, compiler, no_warn_args)
+ commands = self.generate_basic_compiler_args(target, compiler)
# Add custom target dirs as includes automatically, but before
# target-specific include directories.
if target.implicit_include_directories:
@@ -2901,7 +2896,7 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
if use_pch and 'mw' not in compiler.id:
commands += self.get_pch_include_args(compiler, target)

- commands += self._generate_single_compile_target_args(target, compiler, is_generated=False)
+ commands += self._generate_single_compile_target_args(target, compiler)

# Metrowerks compilers require PCH include args to come after intraprocedural analysis args
if use_pch and 'mw' in compiler.id:
@@ -2935,7 +2930,7 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
if use_pch and 'mw' not in compiler.id:
commands += self.get_pch_include_args(compiler, target)

- commands += self._generate_single_compile_target_args(target, compiler, is_generated)
+ commands += self._generate_single_compile_target_args(target, compiler)

# Metrowerks compilers require PCH include args to come after intraprocedural analysis args
if use_pch and 'mw' in compiler.id:
diff --git a/test cases/failing build/1 vala c werror/meson.build b/test cases/failing build/1 vala c werror/meson.build
deleted file mode 100644
index 736d7aa43..000000000
--- a/test cases/failing build/1 vala c werror/meson.build
+++ /dev/null
@@ -1,10 +0,0 @@
-project('valatest', 'c', default_options : 'werror=true')
-
-if find_program('valac', required : false).found()
- add_languages('vala')
- valadeps = [dependency('glib-2.0'), dependency('gobject-2.0')]
- # Must fail due to -Werror and unused variable in C file
- executable('valaprog', 'prog.vala', 'unused-var.c', dependencies : valadeps)
-else
- executable('failprog', 'unused-var.c')
-endif
diff --git a/test cases/failing build/1 vala c werror/prog.vala b/test cases/failing build/1 vala c werror/prog.vala
deleted file mode 100644
index 638e77660..000000000
--- a/test cases/failing build/1 vala c werror/prog.vala
+++ /dev/null
@@ -1,7 +0,0 @@
-class MainProg : GLib.Object {
-
- public static int main(string[] args) {
- stdout.printf("Vala is working.\n");
- return 0;
- }
-}
diff --git a/test cases/failing build/1 vala c werror/unused-var.c b/test cases/failing build/1 vala c werror/unused-var.c
deleted file mode 100644
index 6b85078c9..000000000
--- a/test cases/failing build/1 vala c werror/unused-var.c
+++ /dev/null
@@ -1,8 +0,0 @@
-#warning "something"
-
-int
-somelib(void)
-{
- int unused_var;
- return 33;
-}
diff --git a/test cases/vala/5 target glib/meson.build b/test cases/vala/5 target glib/meson.build
index f285d9f16..089bb3c97 100644
--- a/test cases/vala/5 target glib/meson.build
+++ b/test cases/vala/5 target glib/meson.build
@@ -1,9 +1,5 @@
project('valatest', 'vala', 'c')

-if not meson.is_unity()
- add_global_arguments('-Werror', language : 'c')
-endif
-
valadeps = [dependency('glib-2.0', version : '>=2.32'), dependency('gobject-2.0')]

e = executable('valaprog', 'GLib.Thread.vala', 'retcode.c', dependencies : valadeps)
diff --git a/unittests/linuxliketests.py b/unittests/linuxliketests.py
index 4fcf52e09..a02c99e8f 100644
--- a/unittests/linuxliketests.py
+++ b/unittests/linuxliketests.py
@@ -298,43 +298,6 @@ class LinuxlikeTests(BasePlatformTests):
self.build()
self._run(self.mtest_command)

- def test_vala_c_warnings(self):
- '''
- Test that no warnings are emitted for C code generated by Vala. This
- can't be an ordinary test case because we need to inspect the compiler
- database.
- https://github.com/mesonbuild/meson/issues/864
- '''
- if not shutil.which('valac'):
- raise SkipTest('valac not installed.')
- testdir = os.path.join(self.vala_test_dir, '5 target glib')
- self.init(testdir)
- compdb = self.get_compdb()
- vala_command = None
- c_command = None
- for each in compdb:
- if each['file'].endswith('GLib.Thread.c'):
- vala_command = each['command']
- elif each['file'].endswith('GLib.Thread.vala'):
- continue
- elif each['file'].endswith('retcode.c'):
- c_command = each['command']
- else:
- m = 'Unknown file {!r} in vala_c_warnings test'.format(each['file'])
- raise AssertionError(m)
- self.assertIsNotNone(vala_command)
- self.assertIsNotNone(c_command)
- # -w suppresses all warnings, should be there in Vala but not in C
- self.assertIn(" -w ", vala_command)
- self.assertNotIn(" -w ", c_command)
- # -Wall enables all warnings, should be there in C but not in Vala
- self.assertNotIn(" -Wall ", vala_command)
- self.assertIn(" -Wall ", c_command)
- # -Werror converts warnings to errors, should always be there since it's
- # injected by an unrelated piece of code and the project has werror=true
- self.assertIn(" -Werror ", vala_command)
- self.assertIn(" -Werror ", c_command)
-
@skipIfNoPkgconfig
def test_qtdependency_pkgconfig_detection(self):
'''
--
2.41.0

135 changes: 135 additions & 0 deletions dev-util/meson/meson-1.3.0-r2.ebuild
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# Copyright 2016-2023 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

EAPI=8

PYTHON_COMPAT=( python3_{10..12} pypy3 )
DISTUTILS_USE_PEP517=setuptools

if [[ ${PV} = *9999* ]]; then
EGIT_REPO_URI="https://github.com/mesonbuild/meson"
inherit git-r3
else
inherit verify-sig

MY_PV=${PV/_/}
MY_P=${P/_/}
S=${WORKDIR}/${MY_P}

SRC_URI="
https://github.com/mesonbuild/meson/releases/download/${MY_PV}/${MY_P}.tar.gz
verify-sig? ( https://github.com/mesonbuild/meson/releases/download/${MY_PV}/${MY_P}.tar.gz.asc )
"
BDEPEND="verify-sig? ( sec-keys/openpgp-keys-jpakkane )"
VERIFY_SIG_OPENPGP_KEY_PATH=/usr/share/openpgp-keys/jpakkane.gpg

if [[ ${PV} != *_rc* ]] ; then
KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~loong ~m68k ~mips ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86 ~amd64-linux ~x86-linux ~arm64-macos ~ppc-macos ~x64-macos ~x64-solaris"
fi
fi

inherit bash-completion-r1 distutils-r1 toolchain-funcs

DESCRIPTION="Open source build system"
HOMEPAGE="https://mesonbuild.com/"

LICENSE="Apache-2.0"
SLOT="0"
IUSE="test"
RESTRICT="!test? ( test )"

DEPEND="
test? (
dev-libs/glib:2
dev-libs/gobject-introspection
dev-util/ninja
dev-vcs/git
sys-libs/zlib[static-libs(+)]
virtual/pkgconfig
)
"
RDEPEND="
virtual/pkgconfig
"

PATCHES=(
"${FILESDIR}"/${PN}-1.2.1-python-path.patch

# backport fix for broken configure_file()
"${FILESDIR}"/0001-Only-convert-boolean-values-for-cmake-formats.patch

# backport fix for hiding compiler warnings (such as Modern C) in vala and cython
"${FILESDIR}"/0001-ninja-backend-don-t-hide-all-compiler-warnings-for-t.patch
)

python_prepare_all() {
local disable_unittests=(
# ASAN and sandbox both want control over LD_PRELOAD
# https://bugs.gentoo.org/673016
-e 's/test_generate_gir_with_address_sanitizer/_&/'

# ASAN is unsupported on some targets
# https://bugs.gentoo.org/692822
-e 's/test_pch_with_address_sanitizer/_&/'

# https://github.com/mesonbuild/meson/issues/7203
-e 's/test_templates/_&/'

# Broken due to python2 wrapper
-e 's/test_python_module/_&/'
)

sed -i "${disable_unittests[@]}" unittests/*.py || die

# Broken due to python2 script created by python_wrapper_setup
rm -r "test cases/frameworks/1 boost" || die

distutils-r1_python_prepare_all
}

src_test() {
tc-export PKG_CONFIG
if ${PKG_CONFIG} --exists Qt5Core && ! ${PKG_CONFIG} --exists Qt5Gui; then
ewarn "Found Qt5Core but not Qt5Gui; skipping tests"
else
distutils-r1_src_test
fi
}

python_test() {
(
# test_meson_installed
unset PYTHONDONTWRITEBYTECODE

# https://bugs.gentoo.org/687792
unset PKG_CONFIG

# test_cross_file_system_paths
unset XDG_DATA_HOME

# 'test cases/unit/73 summary' expects 80 columns
export COLUMNS=80

# If JAVA_HOME is not set, meson looks for javac in PATH.
# If javac is in /usr/bin, meson assumes /usr/include is a valid
# JDK include path. Setting JAVA_HOME works around this broken
# autodetection. If no JDK is installed, we should end up with an empty
# value in JAVA_HOME, and the tests should get skipped.
export JAVA_HOME=$(java-config -O 2>/dev/null)

# Call python3 instead of EPYTHON to satisfy test_meson_uninstalled.
python3 run_tests.py
) || die "Testing failed with ${EPYTHON}"
}

python_install_all() {
distutils-r1_python_install_all

insinto /usr/share/vim/vimfiles
doins -r data/syntax-highlighting/vim/{ftdetect,indent,syntax}

insinto /usr/share/zsh/site-functions
doins data/shell-completions/zsh/_meson

dobashcomp data/shell-completions/bash/meson
}

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