patches/glibc/ports-2.10.1/120-i386-x86_64-revert-clone-cfi.patch
author "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Mon Mar 14 22:16:01 2011 +0100 (2011-03-14)
changeset 2335 805e9f2a06fa
permissions -rw-r--r--
samples: new PPC e300c3 sample

Gustavo wrote:

---8<---
Attached my ct-ng e300c3 toolchain config for:

powerpc-e300c3-linux-gnu [l X]
OS : linux-2.6.36.3
Companion libs : gmp-5.0.1 mpfr-3.0.0 ppl-0.10.2 cloog-ppl-0.15.10 mpc-0.8.2 libelf-0.8.13
binutils : binutils-2.21
C compiler : gcc-4.5.2 (C,C++)
C library : eglibc-2_12
Tools :
---8<---

Reported-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
["Yann E. MORIN" : updated to match new config options]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
     1 revert cfi additions to clone on i386/x86_64 to workaround problems in
     2 gcc's unwinder code.  this is not a bug in glibc, it triggers problems
     3 elsewhere.  this cfi code does not gain us a whole lot anyways.
     4 
     5 http://gcc.gnu.org/ml/gcc/2006-12/msg00293.html
     6 
     7 Index: sysdeps/unix/sysv/linux/i386/clone.S
     8 ===================================================================
     9 RCS file: /cvs/glibc/libc/sysdeps/unix/sysv/linux/i386/clone.S,v
    10 retrieving revision 1.27
    11 retrieving revision 1.26
    12 diff -u -p -r1.27 -r1.26
    13 
    14 diff -durN glibc-2.10.1.orig/sysdeps/unix/sysv/linux/i386/clone.S glibc-2.10.1/sysdeps/unix/sysv/linux/i386/clone.S
    15 --- glibc-2.10.1.orig/sysdeps/unix/sysv/linux/i386/clone.S	2006-12-04 00:12:36.000000000 +0100
    16 +++ glibc-2.10.1/sysdeps/unix/sysv/linux/i386/clone.S	2009-11-13 00:49:45.000000000 +0100
    17 @@ -120,9 +120,6 @@
    18  	ret
    19  
    20  L(thread_start):
    21 -	cfi_startproc;
    22 -	/* Clearing frame pointer is insufficient, use CFI.  */
    23 -	cfi_undefined (eip);
    24  	/* Note: %esi is zero.  */
    25  	movl	%esi,%ebp	/* terminate the stack frame */
    26  #ifdef RESET_PID
    27 @@ -155,7 +152,6 @@
    28  	jmp	L(haspid)
    29  	.previous
    30  #endif
    31 -	cfi_endproc;
    32  
    33  	cfi_startproc
    34  PSEUDO_END (BP_SYM (__clone))
    35 diff -durN glibc-2.10.1.orig/sysdeps/unix/sysv/linux/x86_64/clone.S glibc-2.10.1/sysdeps/unix/sysv/linux/x86_64/clone.S
    36 --- glibc-2.10.1.orig/sysdeps/unix/sysv/linux/x86_64/clone.S	2006-12-04 00:12:36.000000000 +0100
    37 +++ glibc-2.10.1/sysdeps/unix/sysv/linux/x86_64/clone.S	2009-11-13 00:49:45.000000000 +0100
    38 @@ -89,9 +89,6 @@
    39  	ret
    40  
    41  L(thread_start):
    42 -	cfi_startproc;
    43 -	/* Clearing frame pointer is insufficient, use CFI.  */
    44 -	cfi_undefined (rip);
    45  	/* Clear the frame pointer.  The ABI suggests this be done, to mark
    46  	   the outermost frame obviously.  */
    47  	xorl	%ebp, %ebp
    48 @@ -116,7 +113,6 @@
    49  	/* Call exit with return value from function call. */
    50  	movq	%rax, %rdi
    51  	call	HIDDEN_JUMPTARGET (_exit)
    52 -	cfi_endproc;
    53  
    54  	cfi_startproc;
    55  PSEUDO_END (BP_SYM (__clone))