[Bug 1848200] Re: gdb not stopping on breakpoint in a 32-bit program

[Manoj Iyer]

This works in Eoan.

$ gdb /tmp/x
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Reading symbols from /tmp/x...
(gdb) b x.c:5
Breakpoint 1 at 0x11ea: file /tmp/x.c, line 5.
(gdb) run
Starting program: /tmp/x 

Breakpoint 1, main () at /tmp/x.c:5
5	   printf("Hello, World!");
(gdb) q
A debugging session is active.

        Inferior 1 [process 10723] will be killed.

Quit anyway? (y or n) y

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https://bugs.launchpad.net/bugs/1848200

Title:
  gdb not stopping on breakpoint in a 32-bit program

Status in gdb package in Ubuntu:
  Confirmed

Bug description:
  After upgrading gdb from 8.1-0ubuntu3 to 8.1-0ubuntu3.1, gdb does not
  stop on breakpoint when running a 32-bit application (on 64-bit
  Ubuntu). This can be reproduced with a simple “hello world” program:

  $ cat hello.c 
  #include <stdio.h>
  int main()
  {
     // printf() displays the string inside quotation
     printf("Hello, World!");
     return 0;
  }
  $ gcc -ggdb -m32 hello.c
  $ gdb a.out
  (gdb) b hello.c:5
  Breakpoint 1 at 0x536: file hello.c, line 5.
  (gdb) run
  Starting program: /home/user/sandbox/a.out 
  warning: Breakpoint address adjusted from 0xf7fd9be0 to 0xfffffffff7fd9be0.
  warning: Breakpoint address adjusted from 0xf7fda195 to 0xfffffffff7fda195.
  warning: Breakpoint address adjusted from 0xf7fdbd1c to 0xfffffffff7fdbd1c.
  warning: Breakpoint address adjusted from 0xf7fdb924 to 0xfffffffff7fdb924.
  warning: Breakpoint address adjusted from 0xf7fe99b3 to 0xfffffffff7fe99b3.
  warning: Breakpoint address adjusted from 0xf7fea401 to 0xfffffffff7fea401.
  warning: Breakpoint address adjusted from 0xf7fea706 to 0xfffffffff7fea706.

  --- (and not stopping nor outputting the text…) ---

  It works well with a 64-bit build (leaving out the gcc’s -m32 option).

  This problem has been already discussed on:
  https://stackoverflow.com/questions/58225562/how-to-fix-hang-in-gdb-
  in-ld-linux-so-2-when-running-a-32-bit-executable-on-a-64

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: gdb 8.1-0ubuntu3.1
  ProcVersionSignature: Ubuntu 4.15.0-65.74-generic 4.15.18
  Uname: Linux 4.15.0-65-generic x86_64
  ApportVersion: 2.20.9-0ubuntu7.7
  Architecture: amd64
  CurrentDesktop: XFCE
  Date: Tue Oct 15 14:37:37 2019
  InstallationDate: Installed on 2015-12-08 (1407 days ago)
  InstallationMedia: Ubuntu-Server 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
  SourcePackage: gdb
  UpgradeStatus: Upgraded to bionic on 2019-06-10 (127 days ago)

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