| Message ID | 771d4c34-534f-228a-3041-2610145c8baa@redhat.com |
|---|---|
| State | Accepted |
| Commit | 76388b236a7089f6ee5dc0a566caa518132f16bd |
| Headers | show |
On 22 Nov 2016 17:43, Florian Weimer wrote: > Due to an accident, we export __longjmp under a public symbol version > for the powerpc32/fpu configuration. > > __longjmp is declared as hidden for internal use. This means that any > reference to this symbol (of which there aren't any right now in > libc.so) will cause the symbol to turn unexported. The reason is that > the linker does not distinguish between hidden definitions and > references. GCC emits a .hidden directive in the __longjmp-referencing > translation unit, and this kills the .symver-based export. > > I propose the removal of the __longjmp export as the simplest fix. > __longjmp is in the implementation namespace and is not used in a public > header. As a result, nothing out there should reference it. > > If this is not acceptable, I'll come up with different approach to > address this. But I prefer to address this issue in this way. > > Tested on a powerpc32/fpu configuration with no regressions. makes sense to me. not sure how any package would end up with a reference to this symbol in their binaries. -mike
On 11/27/2016 07:45 AM, Mike Frysinger wrote: > On 22 Nov 2016 17:43, Florian Weimer wrote: >> Due to an accident, we export __longjmp under a public symbol version >> for the powerpc32/fpu configuration. >> >> __longjmp is declared as hidden for internal use. This means that any >> reference to this symbol (of which there aren't any right now in >> libc.so) will cause the symbol to turn unexported. The reason is that >> the linker does not distinguish between hidden definitions and >> references. GCC emits a .hidden directive in the __longjmp-referencing >> translation unit, and this kills the .symver-based export. >> >> I propose the removal of the __longjmp export as the simplest fix. >> __longjmp is in the implementation namespace and is not used in a public >> header. As a result, nothing out there should reference it. >> >> If this is not acceptable, I'll come up with different approach to >> address this. But I prefer to address this issue in this way. >> >> Tested on a powerpc32/fpu configuration with no regressions. > > makes sense to me. not sure how any package would end up with a reference > to this symbol in their binaries. Thanks. I'll plan to commit this next week, and also the companion patch to add a missing hidden symbol. Steven and Tulio, in case you want to comment, these patches are here: https://sourceware.org/ml/libc-alpha/2016-11/msg00794.html https://sourceware.org/ml/libc-alpha/2016-11/msg00798.html Thanks, Florian
Florian Weimer <fweimer@redhat.com> writes: > Due to an accident, we export __longjmp under a public symbol version > for the powerpc32/fpu configuration. > > __longjmp is declared as hidden for internal use. This means that any > reference to this symbol (of which there aren't any right now in > libc.so) will cause the symbol to turn unexported. The reason is that > the linker does not distinguish between hidden definitions and > references. GCC emits a .hidden directive in the __longjmp-referencing > translation unit, and this kills the .symver-based export. > > I propose the removal of the __longjmp export as the simplest fix. > __longjmp is in the implementation namespace and is not used in a public > header. As a result, nothing out there should reference it. > > If this is not acceptable, I'll come up with different approach to > address this. But I prefer to address this issue in this way. > > Tested on a powerpc32/fpu configuration with no regressions. Makes sense to me too. -- Tulio Magno
On 11/28/2016 02:04 PM, Tulio Magno Quites Machado Filho wrote: > Florian Weimer <fweimer@redhat.com> writes: > >> Due to an accident, we export __longjmp under a public symbol version >> for the powerpc32/fpu configuration. >> >> __longjmp is declared as hidden for internal use. This means that any >> reference to this symbol (of which there aren't any right now in >> libc.so) will cause the symbol to turn unexported. The reason is that >> the linker does not distinguish between hidden definitions and >> references. GCC emits a .hidden directive in the __longjmp-referencing >> translation unit, and this kills the .symver-based export. >> >> I propose the removal of the __longjmp export as the simplest fix. >> __longjmp is in the implementation namespace and is not used in a public >> header. As a result, nothing out there should reference it. >> >> If this is not acceptable, I'll come up with different approach to >> address this. But I prefer to address this issue in this way. >> >> Tested on a powerpc32/fpu configuration with no regressions. > > Makes sense to me too. Thanks, I have committed both patches. Florian
powerpc: Remove unintended __longjmp symbol from ABI 2016-11-22 Florian Weimer <fweimer@redhat.com> * sysdeps/powerpc/powerpc32/fpu/__longjmp.S (__longjmp): Remove version and turn into strong alias. Remove compat symbol. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist (__longjmp): Remove. diff --git a/sysdeps/powerpc/powerpc32/fpu/__longjmp.S b/sysdeps/powerpc/powerpc32/fpu/__longjmp.S index 529e095..c233b88 100644 --- a/sysdeps/powerpc/powerpc32/fpu/__longjmp.S +++ b/sysdeps/powerpc/powerpc32/fpu/__longjmp.S @@ -26,15 +26,13 @@ # include "__longjmp-common.S" #else /* IS_IN (libc) */ -/* Build a versioned object for libc. */ -versioned_symbol (libc, __vmx__longjmp, __longjmp, GLIBC_2_3_4); +strong_alias (__vmx__longjmp, __longjmp) # define __longjmp_symbol __vmx__longjmp # include "__longjmp-common.S" # if defined SHARED && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4) # define __NO_VMX__ # undef JB_SIZE -compat_symbol (libc, __novmx__longjmp, __longjmp, GLIBC_2_0); # undef __longjmp_symbol # define __longjmp_symbol __novmx__longjmp # include "__longjmp-common.S" diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist index 4b0cde8..4ba3146 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist @@ -2112,7 +2112,6 @@ GLIBC_2.3.4 GLIBC_2.3.4 A GLIBC_2.3.4 __chk_fail F GLIBC_2.3.4 __fprintf_chk F GLIBC_2.3.4 __gets_chk F -GLIBC_2.3.4 __longjmp F GLIBC_2.3.4 __memcpy_chk F GLIBC_2.3.4 __memmove_chk F GLIBC_2.3.4 __mempcpy_chk F