| Message ID | 20210823093026.3839645-1-jun.miao@windriver.com |
|---|---|
| State | New |
| Headers | show |
| Series | selftests/x86/sigreturn: Fix error: variably modified 'altstack_data' at file scope | expand |
On 8/23/21 3:30 AM, Jun Miao wrote: > Based on glibc 2.33 -> 2.34, there is one new feature: > > NEWS for version 2.34 > ===================== > > Major new features: > * Add _SC_MINSIGSTKSZ and _SC_SIGSTKSZ. When _DYNAMIC_STACK_SIZE_SOURCE > or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ are no longer > constant on Linux. MINSIGSTKSZ is redefined to sysconf(_SC_MINSIGSTKSZ) > and SIGSTKSZ is redefined to sysconf (_SC_SIGSTKSZ). This supports > dynamic sized register sets for modern architectural features like > Arm SVE. > > Build error with the GNU C Library 2.34: > DEBUG: | sigreturn.c:150:13: error: variably modified 'altstack_data' at file scope > | sigreturn.c:150:13: error: variably modified 'altstack_data' at file scope > DEBUG: | 150 | static char altstack_data[SIGSTKSZ]; > | 150 | static char altstack_data[SIGSTKSZ]; > DEBUG: | | ^~~~~~~~~~~~~ > > Signed-off-by: Jun Miao <jun.miao@windriver.com> > --- > tools/testing/selftests/x86/sigreturn.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) > > diff --git a/tools/testing/selftests/x86/sigreturn.c b/tools/testing/selftests/x86/sigreturn.c > index 57c4f67f16ef..e32ffcc7053d 100644 > --- a/tools/testing/selftests/x86/sigreturn.c > +++ b/tools/testing/selftests/x86/sigreturn.c > @@ -138,9 +138,6 @@ static unsigned short LDT3(int idx) > return (idx << 3) | 7; > } > > -/* Our sigaltstack scratch space. */ > -static char altstack_data[SIGSTKSZ]; > - > static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *), > int flags) > { > @@ -771,7 +768,8 @@ int main() > setup_ldt(); > > stack_t stack = { > - .ss_sp = altstack_data, > + /* Our sigaltstack scratch space. */ > + .ss_sp = malloc (sizeof(char) * SIGSTKSZ), > .ss_size = SIGSTKSZ, > }; > if (sigaltstack(&stack, NULL) != 0) > @@ -872,5 +870,6 @@ int main() > total_nerrs += test_nonstrict_ss(); > #endif > > + free(stack.ss_sp); > return total_nerrs ? 1 : 0; > } > Please see comments on your v2 that includes this change. thanks, -- Shuah
===================== Major new features: * Add _SC_MINSIGSTKSZ and _SC_SIGSTKSZ. When _DYNAMIC_STACK_SIZE_SOURCE or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ are no longer constant on Linux. MINSIGSTKSZ is redefined to sysconf(_SC_MINSIGSTKSZ) and SIGSTKSZ is redefined to sysconf (_SC_SIGSTKSZ). This supports dynamic sized register sets for modern architectural features like Arm SVE. Build error with the GNU C Library 2.34: DEBUG: | sigreturn.c:150:13: error: variably modified 'altstack_data' at file scope | sigreturn.c:150:13: error: variably modified 'altstack_data' at file scope DEBUG: | 150 | static char altstack_data[SIGSTKSZ]; | 150 | static char altstack_data[SIGSTKSZ]; DEBUG: | | ^~~~~~~~~~~~~ Signed-off-by: Jun Miao <jun.miao@windriver.com> --- tools/testing/selftests/x86/sigreturn.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/x86/sigreturn.c b/tools/testing/selftests/x86/sigreturn.c index 57c4f67f16ef..e32ffcc7053d 100644 --- a/tools/testing/selftests/x86/sigreturn.c +++ b/tools/testing/selftests/x86/sigreturn.c @@ -138,9 +138,6 @@ static unsigned short LDT3(int idx) return (idx << 3) | 7; } -/* Our sigaltstack scratch space. */ -static char altstack_data[SIGSTKSZ]; - static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *), int flags) { @@ -771,7 +768,8 @@ int main() setup_ldt(); stack_t stack = { - .ss_sp = altstack_data, + /* Our sigaltstack scratch space. */ + .ss_sp = malloc (sizeof(char) * SIGSTKSZ), .ss_size = SIGSTKSZ, }; if (sigaltstack(&stack, NULL) != 0) @@ -872,5 +870,6 @@ int main() total_nerrs += test_nonstrict_ss(); #endif + free(stack.ss_sp); return total_nerrs ? 1 : 0; }