diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S b/sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S index 47d8c5bc82..283aef1b30 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S @@ -1,5 +1,5 @@ /* Install given context. - Copyright (C) 2008-2016 Free Software Foundation, Inc. + Copyright (C) 2008-2018 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by David S. Miller <davem@davemloft.net>, 2008. @@ -95,6 +95,19 @@ END(__setcontext) weak_alias (__setcontext, setcontext) +/* We add an NOP here to separate between __setcontext/__startcontext. The + wanted behavior that happens is: when unwinding from a function called + inside a makecontext() context, FDE lookup will use '&__startcontext - 1', + then returns NULL for no FDE found, and immediately ends the unwind, in + a normal fashion. + + If this NOP word does not exist, FDE lookup just repeatedly finds + __setcontext's FDE in an infinite loop, due to the convention of using + 'address - 1' for FDE lookup. Modifiying/deleting the below + __startcontext's FDE has no help on this. */ + + nop + /* This is the helper code which gets called if a function which is registered with 'makecontext' returns. In this case we have to install the context listed in the uc_link element of the context |