1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
|
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
|
