| Message ID | 20201103015228.2250547-1-kuhn.chenqun@huawei.com |
|---|---|
| Headers | show |
| Series | fix uninitialized variable warning | expand |
On 11/3/20 2:52 AM, Chen Qun wrote: > After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify > that the statements in the macro must be executed. As a result, some variables > assignment statements in the macro may be considered as unexecuted by the compiler. > > The compiler showed warning: > util/qemu-timer.c: In function ‘timer_mod_anticipate_ns’: > util/qemu-timer.c:474:8: warning: ‘rearm’ may be used uninitialized in this function [-Wmaybe-uninitialized] > 474 | if (rearm) { > | ^ > > Change the default value assignment place to prevented the warning. > > Reported-by: Euler Robot <euler.robot@huawei.com> > Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> > --- > Cc: Paolo Bonzini <pbonzini@redhat.com> > --- > util/qemu-timer.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
On 11/3/20 2:52 AM, Chen Qun wrote: > After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify > that the statements in the macro must be executed. As a result, some variables > assignment statements in the macro may be considered as unexecuted by the compiler. > > The compiler showed warning: > plugins/loader.c: In function ‘plugin_reset_uninstall’: > plugins/loader.c:382:15: warning: ‘ctx’ may be used uninitialized in this function [-Wmaybe-uninitialized] This shouldn't happen as the function returns before (else there is a NULL deref). > 382 | data->ctx = ctx; > | ~~~~~~~~~~^~~~~ > > Add a default value for 'expire_time' to prevented the warning. > > Reported-by: Euler Robot <euler.robot@huawei.com> > Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> > --- > Cc: "Alex Bennée" <alex.bennee@linaro.org> > --- > plugins/loader.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/plugins/loader.c b/plugins/loader.c > index 8ac5dbc20f..88593fe138 100644 > --- a/plugins/loader.c > +++ b/plugins/loader.c > @@ -367,7 +367,7 @@ void plugin_reset_uninstall(qemu_plugin_id_t id, > bool reset) > { > struct qemu_plugin_reset_data *data; > - struct qemu_plugin_ctx *ctx; > + struct qemu_plugin_ctx *ctx = NULL; > > WITH_QEMU_LOCK_GUARD(&plugin.lock) { > ctx = plugin_id_to_ctx_locked(id); >
> -----Original Message----- > From: Philippe Mathieu-Daudé [mailto:philmd@redhat.com] > Sent: Tuesday, November 3, 2020 10:18 AM > To: Chenqun (kuhn) <kuhn.chenqun@huawei.com>; qemu-devel@nongnu.org; > qemu-trivial@nongnu.org > Cc: Alex Bennée <alex.bennee@linaro.org>; Zhanghailiang > <zhang.zhanghailiang@huawei.com>; ganqixin <ganqixin@huawei.com>; Euler > Robot <euler.robot@huawei.com> > Subject: Re: [PATCH 5/6] plugins/loader: fix uninitialized variable warning in > plugin_reset_uninstall() > > On 11/3/20 2:52 AM, Chen Qun wrote: > > After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot > > identify that the statements in the macro must be executed. As a > > result, some variables assignment statements in the macro may be > considered as unexecuted by the compiler. > > > > The compiler showed warning: > > plugins/loader.c: In function ‘plugin_reset_uninstall’: > > plugins/loader.c:382:15: warning: ‘ctx’ may be used uninitialized in > > this function [-Wmaybe-uninitialized] > > This shouldn't happen as the function returns before (else there is a NULL > deref). > Yes, in fact, it shouldn't have happened when the program was running. But after added 'WITH_QEMU_LOCK_GUARD', let the compiler think it might happen. So, we add a default value, make the compiler happy. Thanks, Chen Qun > > 382 | data->ctx = ctx; > > | ~~~~~~~~~~^~~~~ > > > > Add a default value for 'expire_time' to prevented the warning. > > > > Reported-by: Euler Robot <euler.robot@huawei.com> > > Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> > > --- > > Cc: "Alex Bennée" <alex.bennee@linaro.org> > > --- > > plugins/loader.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/plugins/loader.c b/plugins/loader.c index > > 8ac5dbc20f..88593fe138 100644 > > --- a/plugins/loader.c > > +++ b/plugins/loader.c > > @@ -367,7 +367,7 @@ void plugin_reset_uninstall(qemu_plugin_id_t id, > > bool reset) { > > struct qemu_plugin_reset_data *data; > > - struct qemu_plugin_ctx *ctx; > > + struct qemu_plugin_ctx *ctx = NULL; > > > > WITH_QEMU_LOCK_GUARD(&plugin.lock) { > > ctx = plugin_id_to_ctx_locked(id); > >
On Tue, 3 Nov 2020 at 02:07, Chen Qun <kuhn.chenqun@huawei.com> wrote: > > Hi all, > There are some variables initialized warnings reported by the compiler, > even if the default CFLAG for the compiler parameters are uesed. > > This serial has added some default values or changed the assignment places for the variablies to fix them. Hi; if you're reporting/fixing compiler errors/warnings please can you include the compiler version that produced the error in the commit message? This is helpful for telling us whether it's a problem with older compilers or whether this is a new compiler that checks for some things more carefully. thanks -- PMM
> -----Original Message----- > From: Peter Maydell [mailto:peter.maydell@linaro.org] > Sent: Tuesday, November 3, 2020 6:15 PM > To: Chenqun (kuhn) <kuhn.chenqun@huawei.com> > Cc: QEMU Developers <qemu-devel@nongnu.org>; QEMU Trivial > <qemu-trivial@nongnu.org>; Zhanghailiang > <zhang.zhanghailiang@huawei.com>; ganqixin <ganqixin@huawei.com> > Subject: Re: [PATCH 0/6] fix uninitialized variable warning > > On Tue, 3 Nov 2020 at 02:07, Chen Qun <kuhn.chenqun@huawei.com> wrote: > > > > Hi all, > > There are some variables initialized warnings reported by the > > compiler, even if the default CFLAG for the compiler parameters are uesed. > > > > This serial has added some default values or changed the assignment places > for the variablies to fix them. > > > Hi; if you're reporting/fixing compiler errors/warnings please can you include > the compiler version that produced the error in the commit message? This is > helpful for telling us whether it's a problem with older compilers or whether this > is a new compiler that checks for some things more carefully. > Oops, I didn't consider that. These warnings were reported by GCC 9.3, Thanks, Chen Qun
Hi Chen, On Tue, Nov 3, 2020 at 3:53 AM Chen Qun <kuhn.chenqun@huawei.com> wrote: > After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify > that the statements in the macro must be executed. As a result, some > variables > assignment statements in the macro may be considered as unexecuted by the > compiler. > > The compiler showed warning: > hw/rdma/rdma_backend.c: In function ‘rdma_poll_cq’: > hw/rdma/rdma_utils.h:25:5: warning: ‘ne’ may be used uninitialized in this > function [-Wmaybe-uninitialized] > 25 | error_report("%s: " fmt, "rdma", ## __VA_ARGS__) > | ^~~~~~~~~~~~ > hw/rdma/rdma_backend.c:93:12: note: ‘ne’ was declared here > 93 | int i, ne, total_ne = 0; > | ^~ > > Add a default value for 'ne' to prevented the warning. > > Reported-by: Euler Robot <euler.robot@huawei.com> > Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> > --- > Cc: Yuval Shaia <yuval.shaia.ml@gmail.com> > Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com> > --- > hw/rdma/rdma_backend.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c > index 5de010b1fa..2fe4a3501c 100644 > --- a/hw/rdma/rdma_backend.c > +++ b/hw/rdma/rdma_backend.c > @@ -90,7 +90,7 @@ static void clean_recv_mads(RdmaBackendDev *backend_dev) > > static int rdma_poll_cq(RdmaDeviceResources *rdma_dev_res, struct ibv_cq > *ibcq) > { > - int i, ne, total_ne = 0; > + int i, ne = 0, total_ne = 0; > BackendCtx *bctx; > struct ibv_wc wc[2]; > RdmaProtectedGSList *cqe_ctx_list; > -- > 2.27.0 > > Reviewed-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com> Thanks for the fix, Marcel <div dir="ltr"><div>Hi Chen,</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Nov 3, 2020 at 3:53 AM Chen Qun <<a href="mailto:kuhn.chenqun@huawei.com">kuhn.chenqun@huawei.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify<br> that the statements in the macro must be executed. As a result, some variables<br> assignment statements in the macro may be considered as unexecuted by the compiler.<br> <br> The compiler showed warning:<br> hw/rdma/rdma_backend.c: In function ‘rdma_poll_cq’:<br> hw/rdma/rdma_utils.h:25:5: warning: ‘ne’ may be used uninitialized in this function [-Wmaybe-uninitialized]<br> 25 | error_report("%s: " fmt, "rdma", ## __VA_ARGS__)<br> | ^~~~~~~~~~~~<br> hw/rdma/rdma_backend.c:93:12: note: ‘ne’ was declared here<br> 93 | int i, ne, total_ne = 0;<br> | ^~<br> <br> Add a default value for 'ne' to prevented the warning.<br> <br> Reported-by: Euler Robot <<a href="mailto:euler.robot@huawei.com" target="_blank">euler.robot@huawei.com</a>><br> Signed-off-by: Chen Qun <<a href="mailto:kuhn.chenqun@huawei.com" target="_blank">kuhn.chenqun@huawei.com</a>><br> ---<br> Cc: Yuval Shaia <<a href="mailto:yuval.shaia.ml@gmail.com" target="_blank">yuval.shaia.ml@gmail.com</a>><br> Cc: Marcel Apfelbaum <<a href="mailto:marcel.apfelbaum@gmail.com" target="_blank">marcel.apfelbaum@gmail.com</a>><br> ---<br> hw/rdma/rdma_backend.c | 2 +-<br> 1 file changed, 1 insertion(+), 1 deletion(-)<br> <br> diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c<br> index 5de010b1fa..2fe4a3501c 100644<br> --- a/hw/rdma/rdma_backend.c<br> +++ b/hw/rdma/rdma_backend.c<br> @@ -90,7 +90,7 @@ static void clean_recv_mads(RdmaBackendDev *backend_dev)<br> <br> static int rdma_poll_cq(RdmaDeviceResources *rdma_dev_res, struct ibv_cq *ibcq)<br> {<br> - int i, ne, total_ne = 0;<br> + int i, ne = 0, total_ne = 0;<br> BackendCtx *bctx;<br> struct ibv_wc wc[2];<br> RdmaProtectedGSList *cqe_ctx_list;<br> -- <br> 2.27.0<br> <br></blockquote><div><br></div><div><div><div>Reviewed-by: Marcel Apfelbaum <<a href="mailto:marcel.apfelbaum@gmail.com" target="_blank">marcel.apfelbaum@gmail.com</a>></div></div><div><br></div><div>Thanks for the fix,</div><div>Marcel</div></div><div> </div></div></div>
Thanks, Reviewed-by: Yuval Shaia <yuval.shaia.ml@gmail.com> On Tue, 3 Nov 2020 at 03:53, Chen Qun <kuhn.chenqun@huawei.com> wrote: > After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify > that the statements in the macro must be executed. As a result, some > variables > assignment statements in the macro may be considered as unexecuted by the > compiler. > > The compiler showed warning: > hw/rdma/rdma_backend.c: In function ‘rdma_poll_cq’: > hw/rdma/rdma_utils.h:25:5: warning: ‘ne’ may be used uninitialized in this > function [-Wmaybe-uninitialized] > 25 | error_report("%s: " fmt, "rdma", ## __VA_ARGS__) > | ^~~~~~~~~~~~ > hw/rdma/rdma_backend.c:93:12: note: ‘ne’ was declared here > 93 | int i, ne, total_ne = 0; > | ^~ > > Add a default value for 'ne' to prevented the warning. > > Reported-by: Euler Robot <euler.robot@huawei.com> > Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> > --- > Cc: Yuval Shaia <yuval.shaia.ml@gmail.com> > Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com> > --- > hw/rdma/rdma_backend.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c > index 5de010b1fa..2fe4a3501c 100644 > --- a/hw/rdma/rdma_backend.c > +++ b/hw/rdma/rdma_backend.c > @@ -90,7 +90,7 @@ static void clean_recv_mads(RdmaBackendDev *backend_dev) > > static int rdma_poll_cq(RdmaDeviceResources *rdma_dev_res, struct ibv_cq > *ibcq) > { > - int i, ne, total_ne = 0; > + int i, ne = 0, total_ne = 0; > BackendCtx *bctx; > struct ibv_wc wc[2]; > RdmaProtectedGSList *cqe_ctx_list; > -- > 2.27.0 > > <div dir="ltr">Thanks,<div><br><div>Reviewed-by: Yuval Shaia <<a href="mailto:yuval.shaia.ml@gmail.com">yuval.shaia.ml@gmail.com</a>><br></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, 3 Nov 2020 at 03:53, Chen Qun <<a href="mailto:kuhn.chenqun@huawei.com">kuhn.chenqun@huawei.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify<br> that the statements in the macro must be executed. As a result, some variables<br> assignment statements in the macro may be considered as unexecuted by the compiler.<br> <br> The compiler showed warning:<br> hw/rdma/rdma_backend.c: In function ‘rdma_poll_cq’:<br> hw/rdma/rdma_utils.h:25:5: warning: ‘ne’ may be used uninitialized in this function [-Wmaybe-uninitialized]<br> 25 | error_report("%s: " fmt, "rdma", ## __VA_ARGS__)<br> | ^~~~~~~~~~~~<br> hw/rdma/rdma_backend.c:93:12: note: ‘ne’ was declared here<br> 93 | int i, ne, total_ne = 0;<br> | ^~<br> <br> Add a default value for 'ne' to prevented the warning.<br> <br> Reported-by: Euler Robot <<a href="mailto:euler.robot@huawei.com" target="_blank">euler.robot@huawei.com</a>><br> Signed-off-by: Chen Qun <<a href="mailto:kuhn.chenqun@huawei.com" target="_blank">kuhn.chenqun@huawei.com</a>><br> ---<br> Cc: Yuval Shaia <<a href="mailto:yuval.shaia.ml@gmail.com" target="_blank">yuval.shaia.ml@gmail.com</a>><br> Cc: Marcel Apfelbaum <<a href="mailto:marcel.apfelbaum@gmail.com" target="_blank">marcel.apfelbaum@gmail.com</a>><br> ---<br> hw/rdma/rdma_backend.c | 2 +-<br> 1 file changed, 1 insertion(+), 1 deletion(-)<br> <br> diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c<br> index 5de010b1fa..2fe4a3501c 100644<br> --- a/hw/rdma/rdma_backend.c<br> +++ b/hw/rdma/rdma_backend.c<br> @@ -90,7 +90,7 @@ static void clean_recv_mads(RdmaBackendDev *backend_dev)<br> <br> static int rdma_poll_cq(RdmaDeviceResources *rdma_dev_res, struct ibv_cq *ibcq)<br> {<br> - int i, ne, total_ne = 0;<br> + int i, ne = 0, total_ne = 0;<br> BackendCtx *bctx;<br> struct ibv_wc wc[2];<br> RdmaProtectedGSList *cqe_ctx_list;<br> -- <br> 2.27.0<br> <br> </blockquote></div>
Hi all, There are some variables initialized warnings reported by the compiler, even if the default CFLAG for the compiler parameters are uesed. This serial has added some default values or changed the assignment places for the variablies to fix them. Thanks, Chen Qun Chen Qun (6): target/xtensa: fix uninitialized variable warning hw/rdma/rdma_backend: fix uninitialized variable warning in rdma_poll_cq() util/qemu-timer: fix uninitialized variable warning in timer_mod_anticipate_ns() util/qemu-timer: fix uninitialized variable warning for expire_time plugins/loader: fix uninitialized variable warning in plugin_reset_uninstall() migration: fix uninitialized variable warning in migrate_send_rp_req_pages() hw/rdma/rdma_backend.c | 2 +- migration/migration.c | 2 +- plugins/loader.c | 2 +- target/xtensa/translate.c | 2 +- util/qemu-timer.c | 8 +++----- 5 files changed, 7 insertions(+), 9 deletions(-)