Add DWARF2 unwind information.

diff --git a/sysdeps/unix/sysv/linux/x86_64/syscall.S b/sysdeps/unix/sysv/linux/x86_64/syscall.S
index 03144ce..4865836 100644 (file)
--- a/sysdeps/unix/sysv/linux/x86_64/syscall.S
+++ b/sysdeps/unix/sysv/linux/x86_64/syscall.S
@@ -28,7 +28,7 @@
 
        .text
 ENTRY (syscall)
-
+.LFB1:
        movq %rdi, %rax         /* Syscall number -> rax.  */
        movq %rsi, %rdi         /* shift arg1 - arg5.  */
        movq %rdx, %rsi
@@ -39,6 +39,33 @@ ENTRY (syscall)
        cmpq $-4095, %rax       /* Check %rax for error.  */
        jae SYSCALL_ERROR_LABEL /* Jump to error handler if error.  */
 L(pseudo_end):
+.LFE1:
        ret                     /* Return to caller.  */
 
 PSEUDO_END (syscall)
+
+        .section        .eh_frame,"aw",@progbits
+.Lframe1:
+        .long   .LECIE1-.LSCIE1 # Length of Common Information Entry
+.LSCIE1:
+        .long   0x0     # CIE Identifier Tag
+        .byte   0x1     # CIE Version
+        .ascii "\0"     # CIE Augmentation
+        .uleb128 0x1    # CIE Code Alignment Factor
+        .sleb128 -8     # CIE Data Alignment Factor
+        .byte   0x10    # CIE RA Column
+        .byte   0xc     # DW_CFA_def_cfa
+        .uleb128 0x7
+        .uleb128 0x8
+        .byte   0x90    # DW_CFA_offset, column 0x10
+        .uleb128 0x1
+        .align 8
+.LECIE1:
+.LSFDE1:
+        .long   .LEFDE1-.LASFDE1        # FDE Length
+.LASFDE1:
+        .long   .LASFDE1-.Lframe1       # FDE CIE offset
+        .quad   .LFB1   # FDE initial location
+        .quad   .LFE1-.LFB1     # FDE address range
+        .align 8
+.LEFDE1: