[Bug binutils/20984] New: different DOT value in the 'same' place

[pangbw at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=20984

            Bug ID: 20984
           Summary: different DOT value in the 'same' place
           Product: binutils
           Version: 2.22
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: binutils
          Assignee: unassigned at sourceware dot org
          Reporter: pangbw at gmail dot com
  Target Milestone: ---

Created attachment 9708
  --> https://sourceware.org/bugzilla/attachment.cgi?id=9708&action=edit
linker script

Steps to show the issue:
1. cat t.c

#include <stdio.h>

extern char tdata_size [];
extern char tdata_tbss_size [];
extern char tdata_tbss_size2 [];
extern char tdata_tbss_size3 [];

__thread int tls = 0;

int main()
{
  printf("Hello DOT. %d %d %d %d\n",
         tdata_size, tdata_tbss_size, tdata_tbss_size2, tdata_tbss_size3);
  return 0;
}

2. tdata_size, tdata_tbss_size, tdata_tbss_size2 and tdata_tbss_size3 are
defined in the attached link script x.link:

tdata_start = .;
  .tdata          : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
  tdata_size = . - tdata_start;
  .tbss           : {
  *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon)
  tbss_end = .;
  }
  tdata_tbss_size = . - tdata_start;
  tdata_tbss_size2 = tbss_end - tdata_start;
  tdata_tbss_size3 = SIZEOF(.tdata) + SIZEOF(.tbss);


3. gcc -static t.c -Wl,-T x.link
4. ./a.out
Hello DOT. 34 34 90 88

I got this result on Ubuntu precise (12.04.5 LTS), also got the slightly
different result on another different Linux host.

I can understand the difference between tdata_tbss_size2 and tdata_tbss_size3
is caused by alignment, but why tdata_tbss_size is different than
tdata_tbss_size2?

-- 
You are receiving this mail because:
You are on the CC list for the bug.