When running Clang static analyzer on macOS I'm getting:
include/qemu/osdep.h:634:8: error: redefinition of 'iovec'
634 | struct iovec {
| ^
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_iovec_t.h:31:8: note: previous definition is here
31 | struct iovec {
| ^
1 error generated.
Looking at meson-logs.txt, the analyzer enables -Wunused-value
making meson generated code to fail:
Code:
#include <sys/uio.h>
void bar(void) {
sizeof(struct iovec);
}
-----------
stderr:
meson-private/tmpe8_1b_00/testfile.c:3:13: error: expression result unused [-Werror,-Wunused-value]
3 | sizeof(struct iovec);
| ^~~~~~~~~~~~~~~~~~~~
1 error generated.
-----------
Checking for type "struct iovec" : NO
Code:
#include <utmpx.h>
void bar(void) {
sizeof(struct utmpx);
}
-----------
stderr:
meson-private/tmp3n0u490p/testfile.c:3:13: error: expression result unused [-Werror,-Wunused-value]
3 | sizeof(struct utmpx);
| ^~~~~~~~~~~~~~~~~~~~
1 error generated.
-----------
Checking for type "struct utmpx" : NO
Code:
#include <getopt.h>
int main(void) {
/* If it's not defined as a macro, try to use as a symbol */
#ifndef optreset
optreset;
#endif
return 0;
}
-----------
stderr:
meson-private/tmp1rzob_os/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value]
6 | optreset;
| ^~~~~~~~
1 error generated.
-----------
Header "getopt.h" has symbol "optreset" : NO
Code:
#include <vmnet/vmnet.h>
int main(void) {
/* If it's not defined as a macro, try to use as a symbol */
#ifndef VMNET_BRIDGED_MODE
VMNET_BRIDGED_MODE;
#endif
return 0;
}
-----------
stderr:
meson-private/tmpl9jgsxpt/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value]
6 | VMNET_BRIDGED_MODE;
| ^~~~~~~~~~~~~~~~~~
1 error generated.
-----------
Header "vmnet/vmnet.h" has symbol "VMNET_BRIDGED_MODE" with dependency appleframeworks: NO
../meson.build:1174: WARNING: vmnet.framework API is outdated, disabling
Fix by explicitly disabling -Wunused-value from these meson checks.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
RFC: Probably meson should do that in has_header_symbol() / has_type()?
---
meson.build | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/meson.build b/meson.build
index 85f74854735..9d93dcd95d7 100644
--- a/meson.build
+++ b/meson.build
@@ -1189,7 +1189,8 @@ cocoa = dependency('appleframeworks',
vmnet = dependency('appleframeworks', modules: 'vmnet', required: get_option('vmnet'))
if vmnet.found() and not cc.has_header_symbol('vmnet/vmnet.h',
'VMNET_BRIDGED_MODE',
- dependencies: vmnet)
+ dependencies: vmnet,
+ args: '-Wno-unused-value')
vmnet = not_found
if get_option('vmnet').enabled()
error('vmnet.framework API is outdated')
@@ -2713,7 +2714,7 @@ config_host_data.set('CONFIG_RTNETLINK',
config_host_data.set('CONFIG_SYSMACROS',
cc.has_header_symbol('sys/sysmacros.h', 'makedev'))
config_host_data.set('HAVE_OPTRESET',
- cc.has_header_symbol('getopt.h', 'optreset'))
+ cc.has_header_symbol('getopt.h', 'optreset', args: '-Wno-unused-value'))
config_host_data.set('HAVE_IPPROTO_MPTCP',
cc.has_header_symbol('netinet/in.h', 'IPPROTO_MPTCP'))
@@ -2731,10 +2732,12 @@ config_host_data.set('HAVE_BLK_ZONE_REP_CAPACITY',
# has_type
config_host_data.set('CONFIG_IOVEC',
cc.has_type('struct iovec',
- prefix: '#include <sys/uio.h>'))
+ prefix: '#include <sys/uio.h>',
+ args: '-Wno-unused-value'))
config_host_data.set('HAVE_UTMPX',
cc.has_type('struct utmpx',
- prefix: '#include <utmpx.h>'))
+ prefix: '#include <utmpx.h>',
+ args: '-Wno-unused-value'))
config_host_data.set('CONFIG_EVENTFD', cc.links('''
#include <sys/eventfd.h>
--
2.45.2
On Thu Dec 19, 2024 at 4:21 AM AEST, Philippe Mathieu-Daudé wrote:
> When running Clang static analyzer on macOS I'm getting:
>
> include/qemu/osdep.h:634:8: error: redefinition of 'iovec'
> 634 | struct iovec {
> | ^
> /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_iovec_t.h:31:8: note: previous definition is here
> 31 | struct iovec {
> | ^
> 1 error generated.
>
> Looking at meson-logs.txt, the analyzer enables -Wunused-value
> making meson generated code to fail:
>
> Code:
> #include <sys/uio.h>
> void bar(void) {
> sizeof(struct iovec);
> }
> -----------
> stderr:
> meson-private/tmpe8_1b_00/testfile.c:3:13: error: expression result unused [-Werror,-Wunused-value]
> 3 | sizeof(struct iovec);
> | ^~~~~~~~~~~~~~~~~~~~
> 1 error generated.
> -----------
> Checking for type "struct iovec" : NO
>
> Code:
> #include <utmpx.h>
> void bar(void) {
> sizeof(struct utmpx);
> }
> -----------
> stderr:
> meson-private/tmp3n0u490p/testfile.c:3:13: error: expression result unused [-Werror,-Wunused-value]
> 3 | sizeof(struct utmpx);
> | ^~~~~~~~~~~~~~~~~~~~
> 1 error generated.
> -----------
> Checking for type "struct utmpx" : NO
>
> Code:
>
> #include <getopt.h>
> int main(void) {
> /* If it's not defined as a macro, try to use as a symbol */
> #ifndef optreset
> optreset;
> #endif
> return 0;
> }
> -----------
> stderr:
> meson-private/tmp1rzob_os/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value]
> 6 | optreset;
> | ^~~~~~~~
> 1 error generated.
> -----------
> Header "getopt.h" has symbol "optreset" : NO
>
> Code:
>
> #include <vmnet/vmnet.h>
> int main(void) {
> /* If it's not defined as a macro, try to use as a symbol */
> #ifndef VMNET_BRIDGED_MODE
> VMNET_BRIDGED_MODE;
> #endif
> return 0;
> }
> -----------
> stderr:
> meson-private/tmpl9jgsxpt/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value]
> 6 | VMNET_BRIDGED_MODE;
> | ^~~~~~~~~~~~~~~~~~
> 1 error generated.
> -----------
> Header "vmnet/vmnet.h" has symbol "VMNET_BRIDGED_MODE" with dependency appleframeworks: NO
> ../meson.build:1174: WARNING: vmnet.framework API is outdated, disabling
>
> Fix by explicitly disabling -Wunused-value from these meson checks.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> RFC: Probably meson should do that in has_header_symbol() / has_type()?
I don't know about the build system to answer this, but should we
instead disable -Werror on these tests to be a bit more future-proof?
Compilers often add new warnings or catch more cases of existing
warnings.
Alternative would be to keep -Werror but fail the build if a test
throws a warning, but that seems like a lot more work for little
benefit...
Thanks,
Nick
> ---
> meson.build | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/meson.build b/meson.build
> index 85f74854735..9d93dcd95d7 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -1189,7 +1189,8 @@ cocoa = dependency('appleframeworks',
> vmnet = dependency('appleframeworks', modules: 'vmnet', required: get_option('vmnet'))
> if vmnet.found() and not cc.has_header_symbol('vmnet/vmnet.h',
> 'VMNET_BRIDGED_MODE',
> - dependencies: vmnet)
> + dependencies: vmnet,
> + args: '-Wno-unused-value')
> vmnet = not_found
> if get_option('vmnet').enabled()
> error('vmnet.framework API is outdated')
> @@ -2713,7 +2714,7 @@ config_host_data.set('CONFIG_RTNETLINK',
> config_host_data.set('CONFIG_SYSMACROS',
> cc.has_header_symbol('sys/sysmacros.h', 'makedev'))
> config_host_data.set('HAVE_OPTRESET',
> - cc.has_header_symbol('getopt.h', 'optreset'))
> + cc.has_header_symbol('getopt.h', 'optreset', args: '-Wno-unused-value'))
> config_host_data.set('HAVE_IPPROTO_MPTCP',
> cc.has_header_symbol('netinet/in.h', 'IPPROTO_MPTCP'))
>
> @@ -2731,10 +2732,12 @@ config_host_data.set('HAVE_BLK_ZONE_REP_CAPACITY',
> # has_type
> config_host_data.set('CONFIG_IOVEC',
> cc.has_type('struct iovec',
> - prefix: '#include <sys/uio.h>'))
> + prefix: '#include <sys/uio.h>',
> + args: '-Wno-unused-value'))
> config_host_data.set('HAVE_UTMPX',
> cc.has_type('struct utmpx',
> - prefix: '#include <utmpx.h>'))
> + prefix: '#include <utmpx.h>',
> + args: '-Wno-unused-value'))
>
> config_host_data.set('CONFIG_EVENTFD', cc.links('''
> #include <sys/eventfd.h>
On 19/12/24 01:37, Nicholas Piggin wrote:
> On Thu Dec 19, 2024 at 4:21 AM AEST, Philippe Mathieu-Daudé wrote:
>> When running Clang static analyzer on macOS I'm getting:
>>
>> include/qemu/osdep.h:634:8: error: redefinition of 'iovec'
>> 634 | struct iovec {
>> | ^
>> /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_iovec_t.h:31:8: note: previous definition is here
>> 31 | struct iovec {
>> | ^
>> 1 error generated.
>>
>> Looking at meson-logs.txt, the analyzer enables -Wunused-value
>> making meson generated code to fail:
>>
>> Code:
>> #include <sys/uio.h>
>> void bar(void) {
>> sizeof(struct iovec);
>> }
>> -----------
>> stderr:
>> meson-private/tmpe8_1b_00/testfile.c:3:13: error: expression result unused [-Werror,-Wunused-value]
>> 3 | sizeof(struct iovec);
>> | ^~~~~~~~~~~~~~~~~~~~
>> 1 error generated.
>> -----------
>> Checking for type "struct iovec" : NO
>>
>> Code:
>> #include <utmpx.h>
>> void bar(void) {
>> sizeof(struct utmpx);
>> }
>> -----------
>> stderr:
>> meson-private/tmp3n0u490p/testfile.c:3:13: error: expression result unused [-Werror,-Wunused-value]
>> 3 | sizeof(struct utmpx);
>> | ^~~~~~~~~~~~~~~~~~~~
>> 1 error generated.
>> -----------
>> Checking for type "struct utmpx" : NO
>>
>> Code:
>>
>> #include <getopt.h>
>> int main(void) {
>> /* If it's not defined as a macro, try to use as a symbol */
>> #ifndef optreset
>> optreset;
>> #endif
>> return 0;
>> }
>> -----------
>> stderr:
>> meson-private/tmp1rzob_os/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value]
>> 6 | optreset;
>> | ^~~~~~~~
>> 1 error generated.
>> -----------
>> Header "getopt.h" has symbol "optreset" : NO
>>
>> Code:
>>
>> #include <vmnet/vmnet.h>
>> int main(void) {
>> /* If it's not defined as a macro, try to use as a symbol */
>> #ifndef VMNET_BRIDGED_MODE
>> VMNET_BRIDGED_MODE;
>> #endif
>> return 0;
>> }
>> -----------
>> stderr:
>> meson-private/tmpl9jgsxpt/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value]
>> 6 | VMNET_BRIDGED_MODE;
>> | ^~~~~~~~~~~~~~~~~~
>> 1 error generated.
>> -----------
>> Header "vmnet/vmnet.h" has symbol "VMNET_BRIDGED_MODE" with dependency appleframeworks: NO
>> ../meson.build:1174: WARNING: vmnet.framework API is outdated, disabling
>>
>> Fix by explicitly disabling -Wunused-value from these meson checks.
>>
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>> ---
>> RFC: Probably meson should do that in has_header_symbol() / has_type()?
>
> I don't know about the build system to answer this, but should we
> instead disable -Werror on these tests to be a bit more future-proof?
> Compilers often add new warnings or catch more cases of existing
> warnings.
Sorry, I didn't mean to include this patch in this series. I happen
to have my series on top of it and forgot to change the base commit.
> Alternative would be to keep -Werror but fail the build if a test
> throws a warning, but that seems like a lot more work for little
> benefit...
I'm trying to fix it on the meson side with this:
-- >8 --
diff --git a/mesonbuild/compilers/mixins/clike.py
b/mesonbuild/compilers/mixins/clike.py
index d56547b47..9d6957973 100644
--- a/mesonbuild/compilers/mixins/clike.py
+++ b/mesonbuild/compilers/mixins/clike.py
@@ -360,7 +360,7 @@ class CLikeCompiler(Compiler):
int main(void) {{
/* If it's not defined as a macro, try to use as a symbol */
#ifndef {symbol}
- {symbol};
+ (void) {symbol};
#endif
return 0;
}}'''
@@ -885,7 +885,8 @@ class CLikeCompiler(Compiler):
dependencies: T.Optional[T.List['Dependency']] =
None) -> T.Tuple[bool, bool]:
t = f'''{prefix}
void bar(void) {{
- (void) sizeof({typename});
+ size_t foo = sizeof({typename});
+ (void) foo;
}}'''
return self.compiles(t, env, extra_args=extra_args,
dependencies=dependencies)
---
On 12/19/24 09:39, Philippe Mathieu-Daudé wrote:
> @@ -885,7 +885,8 @@ class CLikeCompiler(Compiler):
> dependencies: T.Optional[T.List['Dependency']] = None) -> T.Tuple[bool,
> bool]:
> t = f'''{prefix}
> void bar(void) {{
> - (void) sizeof({typename});
> + size_t foo = sizeof({typename});
> + (void) foo;
> }}'''
As I mentioned elsewhere, sizeof is a compile-time constant.
The function wrapper is getting in the way. This can be just
unsigned long foo = sizeof({typename});
I.e. initialization of a global variable, with no need for <stddef.h> or any other system
header for size_t.
r~
© 2016 - 2025 Red Hat, Inc.