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From: Brian Drummond <brian@shapes.demon.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: GNAT compiler versions and addr2line
Date: Wed, 22 Aug 2018 21:10:11 -0000 (UTC)
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Date: 2018-08-22T21:10:11+00:00
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On Wed, 22 Aug 2018 13:01:58 +0000, Phil wrote:

> Hi,
> 
> I'm having problems getting useful debugging data from some GNAT
> versions.  If I use the Debian FSF version (6.3.0), I get very little
> useful unless running inside gdb.  In particular, the trace addresses
> don't resolve to anything through addr2line.
> 
Basically Debian changed its policy (possibly for security reasons) 
regarding Address Space Randomisation and position-independent 
executables - not sure exactly what, perhaps they turned on PIE by 
default, to allow address space randomisation. I've seen all those 5555s 
in addresses so treated... (not so random, then?)

Anyway, apparently addr2line doesn't work so well with random addresses...

My "solution" is to suppress PIE, at least while debugging.

gpr snippet...

   package Compiler is
      for Default_Switches ("Ada") use ("-g", "-O1", "-gnatafo", "-
gnatq", "-gnatQ", "-gnateE");
   end Compiler;
   package Binder is
      for Default_Switches ("Ada") use ("-E");
   end Binder;
   package Linker is
      for Default_Switches ("Ada") use ("-g", "-no-pie");
   end Linker;

At the very least, -no-pie to the linker is necessary,  some of the 
others are necessary to get the traceback.

Still on the lookout for a better answer too.

-- Brian