From 2bc2d8e82350d451426c6b4fe5ab116f9fc3c205 Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Fri, 14 Dec 2012 10:46:54 -0500 Subject: [PATCH] tile: fix DWARF bug in clone() for created thread Previously, we would see a bad frame in the gdb backtrace output, e.g.: (gdb) bt #0 foo () at foo.c:5 #1 0x000000aaaab68ee8 in start_thread () from /lib/libpthread.so.0 #2 0x000000aaaad01c88 in clone () from /lib/libc.so.6 #3 0x0000000000000000 in ?? () With this change the bogus frame #3 is gone and we have the same output as x86 does for the same program. --- ports/ChangeLog.tile | 4 ++++ ports/sysdeps/unix/sysv/linux/tile/nptl/clone.S | 3 ++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/ports/ChangeLog.tile b/ports/ChangeLog.tile index 67dc50c289..da39a6efae 100644 --- a/ports/ChangeLog.tile +++ b/ports/ChangeLog.tile @@ -1,3 +1,7 @@ +2012-12-14 Chris Metcalf + + * sysdeps/unix/sysv/linux/tile/nptl/clone.S: Fix DWARF info. + 2012-11-29 Chris Metcalf * sysdeps/tile/s_fmaf.c: Remove redundant #defines now provided diff --git a/ports/sysdeps/unix/sysv/linux/tile/nptl/clone.S b/ports/sysdeps/unix/sysv/linux/tile/nptl/clone.S index de4fa136d3..27592cc824 100644 --- a/ports/sysdeps/unix/sysv/linux/tile/nptl/clone.S +++ b/ports/sysdeps/unix/sysv/linux/tile/nptl/clone.S @@ -160,6 +160,8 @@ ENTRY (__clone) r32: the user function pointer */ .Lthread_start: + cfi_def_cfa_offset (FRAME_SIZE) + cfi_undefined (lr) /* Check and see if we need to reset the PID, which we do if CLONE_THREAD isn't set, i.e. we're not staying in the thread group. If CLONE_VM is set, we're doing some kind of thread-like clone, @@ -167,7 +169,6 @@ ENTRY (__clone) in getpid(). Otherwise (if CLONE_VM isn't set), it's a fork-like clone, and we go ahead and write the cached values from the true system pid (retrieved via __NR_getpid syscall). */ - cfi_def_cfa_offset (FRAME_SIZE) #ifdef __tilegx__ { moveli r0, hw1_last(CLONE_VM)