* commit 16adc58e73f3 (stdlib: Fix data race in __run_exit_handlers [BZ #27749])
@ 2023-02-12 23:43 Rasmus Villemoes
2023-02-13 1:54 ` Vitaly Buka
2023-02-13 6:01 ` Vitaly Buka
0 siblings, 2 replies; 7+ messages in thread
From: Rasmus Villemoes @ 2023-02-12 23:43 UTC (permalink / raw)
To: libc-alpha; +Cc: Vitaly Buka, Adhemerval Zanella
I think the commit in $subject is broken. I was browsing through the
atexit handling code and stumbled on something which is always a code
smell, namely the pattern
if (whatever)
continue;
at the end of a loop.
And indeed, since we no longer jump back to the outer loop and refetch
the list head, one can observe a change in behavior. This program:
#include <stdio.h>
#include <stdlib.h>
void h(void)
{
printf("third: %s()\n", __func__);
}
void j(void)
{
printf("second: %s()\n", __func__);
}
void g(void)
{
printf("first: %s()\n", __func__);
atexit(h);
atexit(j);
}
void f(void) {
static int c;
printf("%s: %d\n", __func__, ++c);
}
int main(int argc, char *argv[])
{
int i;
/*
* Stuff the "struct exit_function_list" with dummy callbacks;
* 30 may need to be adjusted depending on how many atexit()
* registrations libc itself does.
*/
for (i = 0; i < 30; ++i)
atexit(f);
/* Register one more, to fill the last slot in struct
exit_function_list. */
atexit(g);
return 0;
}
used to print
first: g()
second: j()
third: h()
f: 1
...
f: 30
but now it instead prints
first: g()
third: h()
f: 1
...
f: 30
second: j()
Rasmus
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: commit 16adc58e73f3 (stdlib: Fix data race in __run_exit_handlers [BZ #27749]) 2023-02-12 23:43 commit 16adc58e73f3 (stdlib: Fix data race in __run_exit_handlers [BZ #27749]) Rasmus Villemoes @ 2023-02-13 1:54 ` Vitaly Buka 2023-02-13 5:57 ` [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] Vitaly Buka 2023-02-13 6:01 ` Vitaly Buka 1 sibling, 1 reply; 7+ messages in thread From: Vitaly Buka @ 2023-02-13 1:54 UTC (permalink / raw) To: Rasmus Villemoes; +Cc: libc-alpha, Adhemerval Zanella [-- Attachment #1: Type: text/plain, Size: 1637 bytes --] Not sure how this happened, but it was not on my patch https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html On Sun, 12 Feb 2023 at 15:44, Rasmus Villemoes <rasmus.villemoes@prevas.dk> wrote: > I think the commit in $subject is broken. I was browsing through the > atexit handling code and stumbled on something which is always a code > smell, namely the pattern > > if (whatever) > continue; > > at the end of a loop. > > And indeed, since we no longer jump back to the outer loop and refetch > the list head, one can observe a change in behavior. This program: > > #include <stdio.h> > #include <stdlib.h> > > void h(void) > { > printf("third: %s()\n", __func__); > } > void j(void) > { > printf("second: %s()\n", __func__); > } > > void g(void) > { > printf("first: %s()\n", __func__); > atexit(h); > atexit(j); > } > void f(void) { > static int c; > printf("%s: %d\n", __func__, ++c); > } > > int main(int argc, char *argv[]) > { > int i; > > /* > * Stuff the "struct exit_function_list" with dummy callbacks; > * 30 may need to be adjusted depending on how many atexit() > * registrations libc itself does. > */ > for (i = 0; i < 30; ++i) > atexit(f); > > /* Register one more, to fill the last slot in struct > exit_function_list. */ > atexit(g); > > return 0; > } > > used to print > > first: g() > second: j() > third: h() > f: 1 > ... > f: 30 > > but now it instead prints > > first: g() > third: h() > f: 1 > ... > f: 30 > second: j() > > > Rasmus > ^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] 2023-02-13 1:54 ` Vitaly Buka @ 2023-02-13 5:57 ` Vitaly Buka 0 siblings, 0 replies; 7+ messages in thread From: Vitaly Buka @ 2023-02-13 5:57 UTC (permalink / raw) To: libc-alpha; +Cc: Vitaly Buka Post review removal of "goto restart" from https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html introduced a bug when some atexit handers skipped. Signed-off-by: Vitaly Buka <vitalybuka@google.com> --- stdlib/Makefile | 1 + stdlib/exit.c | 7 +++- stdlib/test-atexit-recursive.c | 72 ++++++++++++++++++++++++++++++++++ 3 files changed, 78 insertions(+), 2 deletions(-) create mode 100644 stdlib/test-atexit-recursive.c diff --git a/stdlib/Makefile b/stdlib/Makefile index 83391d00c1..8f80571d76 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -171,6 +171,7 @@ tests := \ test-a64l \ test-at_quick_exit-race \ test-atexit-race \ + test-atexit-recursive \ test-bz22786 \ test-canon \ test-canon2 \ diff --git a/stdlib/exit.c b/stdlib/exit.c index 6b1eed6445..1cd0bdfe94 100644 --- a/stdlib/exit.c +++ b/stdlib/exit.c @@ -51,7 +51,10 @@ __run_exit_handlers (int status, struct exit_function_list **listp, exit (). */ while (true) { - struct exit_function_list *cur = *listp; + struct exit_function_list *cur; + + restart: + cur = *listp; if (cur == NULL) { @@ -113,7 +116,7 @@ __run_exit_handlers (int status, struct exit_function_list **listp, if (__glibc_unlikely (new_exitfn_called != __new_exitfn_called)) /* The last exit function, or another thread, has registered more exit functions. Start the loop over. */ - continue; + goto restart; } *listp = cur->next; diff --git a/stdlib/test-atexit-recursive.c b/stdlib/test-atexit-recursive.c new file mode 100644 index 0000000000..ca832941fe --- /dev/null +++ b/stdlib/test-atexit-recursive.c @@ -0,0 +1,72 @@ +/* Support file for atexit/exit, etc. race tests (BZ #27749). + Copyright (C) 2021-2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +/* Check that atexit handler registed from another handler still called. */ + +#include <stdio.h> +#include <stdlib.h> +#include <support/check.h> +#include <support/xunistd.h> +#include <sys/wait.h> +#include <unistd.h> + +static void +atexit_cb (void) { +} + +static void +atexit_last (void) { + _exit (1); +} + +static void +atexit_recursive (void) { + atexit(&atexit_cb); + atexit(&atexit_last); +} + +_Noreturn static void +test_and_exit (int count) +{ + for (int i = 0; i < count; ++i) + atexit(&atexit_cb); + atexit(&atexit_recursive); + exit (0); +} + +static int +do_test (void) +{ + for (int i = 0; i < 100; ++i) + if (xfork () == 0) + test_and_exit (i); + + for (int i = 0; i < 100; ++i) + { + int status; + xwaitpid (0, &status, 0); + if (!WIFEXITED (status)) + FAIL_EXIT1 ("Failed iterations %d", i); + TEST_COMPARE (WEXITSTATUS (status), 1); + } + + return 0; +} + +#define TEST_FUNCTION do_test +#include <support/test-driver.c> -- 2.39.1.581.gbfd45094c4-goog ^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] 2023-02-12 23:43 commit 16adc58e73f3 (stdlib: Fix data race in __run_exit_handlers [BZ #27749]) Rasmus Villemoes 2023-02-13 1:54 ` Vitaly Buka @ 2023-02-13 6:01 ` Vitaly Buka 2023-02-13 16:27 ` Adhemerval Zanella Netto 1 sibling, 1 reply; 7+ messages in thread From: Vitaly Buka @ 2023-02-13 6:01 UTC (permalink / raw) To: libc-alpha; +Cc: Rasmus Villemoes, Adhemerval Zanella, Vitaly Buka Post review removal of "goto restart" from https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html introduced a bug when some atexit handers skipped. Signed-off-by: Vitaly Buka <vitalybuka@google.com> --- stdlib/Makefile | 1 + stdlib/exit.c | 7 +++- stdlib/test-atexit-recursive.c | 72 ++++++++++++++++++++++++++++++++++ 3 files changed, 78 insertions(+), 2 deletions(-) create mode 100644 stdlib/test-atexit-recursive.c diff --git a/stdlib/Makefile b/stdlib/Makefile index 83391d00c1..8f80571d76 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -171,6 +171,7 @@ tests := \ test-a64l \ test-at_quick_exit-race \ test-atexit-race \ + test-atexit-recursive \ test-bz22786 \ test-canon \ test-canon2 \ diff --git a/stdlib/exit.c b/stdlib/exit.c index 6b1eed6445..1cd0bdfe94 100644 --- a/stdlib/exit.c +++ b/stdlib/exit.c @@ -51,7 +51,10 @@ __run_exit_handlers (int status, struct exit_function_list **listp, exit (). */ while (true) { - struct exit_function_list *cur = *listp; + struct exit_function_list *cur; + + restart: + cur = *listp; if (cur == NULL) { @@ -113,7 +116,7 @@ __run_exit_handlers (int status, struct exit_function_list **listp, if (__glibc_unlikely (new_exitfn_called != __new_exitfn_called)) /* The last exit function, or another thread, has registered more exit functions. Start the loop over. */ - continue; + goto restart; } *listp = cur->next; diff --git a/stdlib/test-atexit-recursive.c b/stdlib/test-atexit-recursive.c new file mode 100644 index 0000000000..ca832941fe --- /dev/null +++ b/stdlib/test-atexit-recursive.c @@ -0,0 +1,72 @@ +/* Support file for atexit/exit, etc. race tests (BZ #27749). + Copyright (C) 2021-2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +/* Check that atexit handler registed from another handler still called. */ + +#include <stdio.h> +#include <stdlib.h> +#include <support/check.h> +#include <support/xunistd.h> +#include <sys/wait.h> +#include <unistd.h> + +static void +atexit_cb (void) { +} + +static void +atexit_last (void) { + _exit (1); +} + +static void +atexit_recursive (void) { + atexit(&atexit_cb); + atexit(&atexit_last); +} + +_Noreturn static void +test_and_exit (int count) +{ + for (int i = 0; i < count; ++i) + atexit(&atexit_cb); + atexit(&atexit_recursive); + exit (0); +} + +static int +do_test (void) +{ + for (int i = 0; i < 100; ++i) + if (xfork () == 0) + test_and_exit (i); + + for (int i = 0; i < 100; ++i) + { + int status; + xwaitpid (0, &status, 0); + if (!WIFEXITED (status)) + FAIL_EXIT1 ("Failed iterations %d", i); + TEST_COMPARE (WEXITSTATUS (status), 1); + } + + return 0; +} + +#define TEST_FUNCTION do_test +#include <support/test-driver.c> -- 2.39.1.581.gbfd45094c4-goog ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] 2023-02-13 6:01 ` Vitaly Buka @ 2023-02-13 16:27 ` Adhemerval Zanella Netto 2023-02-18 20:53 ` Vitaly Buka 0 siblings, 1 reply; 7+ messages in thread From: Adhemerval Zanella Netto @ 2023-02-13 16:27 UTC (permalink / raw) To: Vitaly Buka, libc-alpha; +Cc: Rasmus Villemoes On 13/02/23 03:01, Vitaly Buka wrote: > Post review removal of "goto restart" from > https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html > introduced a bug when some atexit handers skipped. > > Signed-off-by: Vitaly Buka <vitalybuka@google.com> Some minor issues on testcase style, besides that LGTM. I am trying to recall why I have pushed a slight different patch than the one you posted on maillist (most likely my mistake). > --- > stdlib/Makefile | 1 + > stdlib/exit.c | 7 +++- > stdlib/test-atexit-recursive.c | 72 ++++++++++++++++++++++++++++++++++ > 3 files changed, 78 insertions(+), 2 deletions(-) > create mode 100644 stdlib/test-atexit-recursive.c > > diff --git a/stdlib/Makefile b/stdlib/Makefile > index 83391d00c1..8f80571d76 100644 > --- a/stdlib/Makefile > +++ b/stdlib/Makefile > @@ -171,6 +171,7 @@ tests := \ > test-a64l \ > test-at_quick_exit-race \ > test-atexit-race \ > + test-atexit-recursive \ > test-bz22786 \ > test-canon \ > test-canon2 \ > diff --git a/stdlib/exit.c b/stdlib/exit.c > index 6b1eed6445..1cd0bdfe94 100644 > --- a/stdlib/exit.c > +++ b/stdlib/exit.c > @@ -51,7 +51,10 @@ __run_exit_handlers (int status, struct exit_function_list **listp, > exit (). */ > while (true) > { > - struct exit_function_list *cur = *listp; > + struct exit_function_list *cur; > + > + restart: > + cur = *listp; > > if (cur == NULL) > { > @@ -113,7 +116,7 @@ __run_exit_handlers (int status, struct exit_function_list **listp, > if (__glibc_unlikely (new_exitfn_called != __new_exitfn_called)) > /* The last exit function, or another thread, has registered > more exit functions. Start the loop over. */ > - continue; > + goto restart; > } > > *listp = cur->next; > diff --git a/stdlib/test-atexit-recursive.c b/stdlib/test-atexit-recursive.c > new file mode 100644 > index 0000000000..ca832941fe > --- /dev/null > +++ b/stdlib/test-atexit-recursive.c > @@ -0,0 +1,72 @@ > +/* Support file for atexit/exit, etc. race tests (BZ #27749). > + Copyright (C) 2021-2023 Free Software Foundation, Inc. Just 2023 here. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <https://www.gnu.org/licenses/>. */ > + > +/* Check that atexit handler registed from another handler still called. */ > + > +#include <stdio.h> > +#include <stdlib.h> > +#include <support/check.h> > +#include <support/xunistd.h> > +#include <sys/wait.h> > +#include <unistd.h> > + > +static void > +atexit_cb (void) { > +} > + Open brackets in new line: func (void) { > +static void > +atexit_last (void) { > + _exit (1); > +} > + > +static void > +atexit_recursive (void) { > + atexit(&atexit_cb); Space after function name. > + atexit(&atexit_last); > +} > + > +_Noreturn static void > +test_and_exit (int count) > +{ > + for (int i = 0; i < count; ++i) > + atexit(&atexit_cb); > + atexit(&atexit_recursive); > + exit (0); > +} > + > +static int > +do_test (void) > +{ > + for (int i = 0; i < 100; ++i) > + if (xfork () == 0) > + test_and_exit (i); > + > + for (int i = 0; i < 100; ++i) > + { > + int status; > + xwaitpid (0, &status, 0); > + if (!WIFEXITED (status)) > + FAIL_EXIT1 ("Failed iterations %d", i); > + TEST_COMPARE (WEXITSTATUS (status), 1); > + } > + > + return 0; > +} > + > +#define TEST_FUNCTION do_test No need to define TEST_FUNCTION. > +#include <support/test-driver.c> ^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] 2023-02-13 16:27 ` Adhemerval Zanella Netto @ 2023-02-18 20:53 ` Vitaly Buka 2023-02-20 12:20 ` Adhemerval Zanella Netto 0 siblings, 1 reply; 7+ messages in thread From: Vitaly Buka @ 2023-02-18 20:53 UTC (permalink / raw) To: libc-alpha; +Cc: Rasmus Villemoes, Adhemerval Zanella, Vitaly Buka Post review removal of "goto restart" from https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html introduced a bug when some atexit handers skipped. Signed-off-by: Vitaly Buka <vitalybuka@google.com> --- stdlib/Makefile | 1 + stdlib/exit.c | 7 +++- stdlib/test-atexit-recursive.c | 75 ++++++++++++++++++++++++++++++++++ 3 files changed, 81 insertions(+), 2 deletions(-) create mode 100644 stdlib/test-atexit-recursive.c diff --git a/stdlib/Makefile b/stdlib/Makefile index ff5096ad1b..cd32f53b56 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -171,6 +171,7 @@ tests := \ test-a64l \ test-at_quick_exit-race \ test-atexit-race \ + test-atexit-recursive \ test-bz22786 \ test-canon \ test-canon2 \ diff --git a/stdlib/exit.c b/stdlib/exit.c index 6b1eed6445..1cd0bdfe94 100644 --- a/stdlib/exit.c +++ b/stdlib/exit.c @@ -51,7 +51,10 @@ __run_exit_handlers (int status, struct exit_function_list **listp, exit (). */ while (true) { - struct exit_function_list *cur = *listp; + struct exit_function_list *cur; + + restart: + cur = *listp; if (cur == NULL) { @@ -113,7 +116,7 @@ __run_exit_handlers (int status, struct exit_function_list **listp, if (__glibc_unlikely (new_exitfn_called != __new_exitfn_called)) /* The last exit function, or another thread, has registered more exit functions. Start the loop over. */ - continue; + goto restart; } *listp = cur->next; diff --git a/stdlib/test-atexit-recursive.c b/stdlib/test-atexit-recursive.c new file mode 100644 index 0000000000..0596b9763b --- /dev/null +++ b/stdlib/test-atexit-recursive.c @@ -0,0 +1,75 @@ +/* Support file for atexit/exit, etc. race tests (BZ #27749). + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +/* Check that atexit handler registed from another handler still called. */ + +#include <stdio.h> +#include <stdlib.h> +#include <support/check.h> +#include <support/xunistd.h> +#include <sys/wait.h> +#include <unistd.h> + +static void +atexit_cb (void) +{ +} + +static void +atexit_last (void) +{ + _exit (1); +} + +static void +atexit_recursive (void) +{ + atexit (&atexit_cb); + atexit (&atexit_last); +} + +_Noreturn static void +test_and_exit (int count) +{ + for (int i = 0; i < count; ++i) + atexit (&atexit_cb); + atexit (&atexit_recursive); + exit (0); +} + +static int +do_test (void) +{ + for (int i = 0; i < 100; ++i) + if (xfork () == 0) + test_and_exit (i); + + for (int i = 0; i < 100; ++i) + { + int status; + xwaitpid (0, &status, 0); + if (!WIFEXITED (status)) + FAIL_EXIT1 ("Failed iterations %d", i); + TEST_COMPARE (WEXITSTATUS (status), 1); + } + + return 0; +} + +#define TEST_FUNCTION do_test +#include <support/test-driver.c> -- 2.39.2.637.g21b0678d19-goog ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] 2023-02-18 20:53 ` Vitaly Buka @ 2023-02-20 12:20 ` Adhemerval Zanella Netto 0 siblings, 0 replies; 7+ messages in thread From: Adhemerval Zanella Netto @ 2023-02-20 12:20 UTC (permalink / raw) To: Vitaly Buka, libc-alpha; +Cc: Rasmus Villemoes On 18/02/23 17:53, Vitaly Buka wrote: > Post review removal of "goto restart" from > https://sourceware.org/pipermail/libc-alpha/2021-April/125470.html > introduced a bug when some atexit handers skipped. > > Signed-off-by: Vitaly Buka <vitalybuka@google.com> LGTM, thanks. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> > --- > stdlib/Makefile | 1 + > stdlib/exit.c | 7 +++- > stdlib/test-atexit-recursive.c | 75 ++++++++++++++++++++++++++++++++++ > 3 files changed, 81 insertions(+), 2 deletions(-) > create mode 100644 stdlib/test-atexit-recursive.c > > diff --git a/stdlib/Makefile b/stdlib/Makefile > index ff5096ad1b..cd32f53b56 100644 > --- a/stdlib/Makefile > +++ b/stdlib/Makefile > @@ -171,6 +171,7 @@ tests := \ > test-a64l \ > test-at_quick_exit-race \ > test-atexit-race \ > + test-atexit-recursive \ > test-bz22786 \ > test-canon \ > test-canon2 \ > diff --git a/stdlib/exit.c b/stdlib/exit.c > index 6b1eed6445..1cd0bdfe94 100644 > --- a/stdlib/exit.c > +++ b/stdlib/exit.c > @@ -51,7 +51,10 @@ __run_exit_handlers (int status, struct exit_function_list **listp, > exit (). */ > while (true) > { > - struct exit_function_list *cur = *listp; > + struct exit_function_list *cur; > + > + restart: > + cur = *listp; > > if (cur == NULL) > { > @@ -113,7 +116,7 @@ __run_exit_handlers (int status, struct exit_function_list **listp, > if (__glibc_unlikely (new_exitfn_called != __new_exitfn_called)) > /* The last exit function, or another thread, has registered > more exit functions. Start the loop over. */ > - continue; > + goto restart; > } > > *listp = cur->next; > diff --git a/stdlib/test-atexit-recursive.c b/stdlib/test-atexit-recursive.c > new file mode 100644 > index 0000000000..0596b9763b > --- /dev/null > +++ b/stdlib/test-atexit-recursive.c > @@ -0,0 +1,75 @@ > +/* Support file for atexit/exit, etc. race tests (BZ #27749). > + Copyright (C) 2023 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <https://www.gnu.org/licenses/>. */ > + > +/* Check that atexit handler registed from another handler still called. */ > + > +#include <stdio.h> > +#include <stdlib.h> > +#include <support/check.h> > +#include <support/xunistd.h> > +#include <sys/wait.h> > +#include <unistd.h> > + > +static void > +atexit_cb (void) > +{ > +} > + > +static void > +atexit_last (void) > +{ > + _exit (1); > +} > + > +static void > +atexit_recursive (void) > +{ > + atexit (&atexit_cb); > + atexit (&atexit_last); > +} > + > +_Noreturn static void > +test_and_exit (int count) > +{ > + for (int i = 0; i < count; ++i) > + atexit (&atexit_cb); > + atexit (&atexit_recursive); > + exit (0); > +} > + > +static int > +do_test (void) > +{ > + for (int i = 0; i < 100; ++i) > + if (xfork () == 0) > + test_and_exit (i); > + > + for (int i = 0; i < 100; ++i) > + { > + int status; > + xwaitpid (0, &status, 0); > + if (!WIFEXITED (status)) > + FAIL_EXIT1 ("Failed iterations %d", i); > + TEST_COMPARE (WEXITSTATUS (status), 1); > + } > + > + return 0; > +} > + > +#define TEST_FUNCTION do_test > +#include <support/test-driver.c> ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2023-02-20 12:20 UTC | newest] Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-02-12 23:43 commit 16adc58e73f3 (stdlib: Fix data race in __run_exit_handlers [BZ #27749]) Rasmus Villemoes 2023-02-13 1:54 ` Vitaly Buka 2023-02-13 5:57 ` [PATCH] stdlib: Undo post review change to 16adc58e73f3 [BZ #27749] Vitaly Buka 2023-02-13 6:01 ` Vitaly Buka 2023-02-13 16:27 ` Adhemerval Zanella Netto 2023-02-18 20:53 ` Vitaly Buka 2023-02-20 12:20 ` Adhemerval Zanella Netto
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).