Re: [PATCH][gdb/testsuite] Fix ada tests with -fPIE/-pie

[Tom de Vries <tdevries@suse.de>]

On 07-08-19 16:18, Tom Tromey wrote:
>>>>>> "Tom" == Tom de Vries <tdevries@suse.de> writes:
> 
> Tom> When running the gdb testsuite with target board unix/-fPIE/-pie, the
> Tom> resulting ada executables are not PIE executables, because gnatmake doesn't
> Tom> recognize -pie, and consequently doesn't pass it to gnatlink.
> 
> Tom> Fix this by replacing "-pie" with "-largs -pie -margs" for ada test-cases in
> Tom> gdb_default_target_compile, and doing the same for -no-pie.
> 
> I think this is a good idea overall.
> 
> However, is gdb_default_target_compile still used?  And if so, by what
> path?

I'm using dejagnu 1.6.1, and that one does not have find_go_linker. So,
use_gdb_compile is set to 1 and we get:
...
if {$use_gdb_compile} {
    catch {rename default_target_compile {}}
    rename gdb_default_target_compile default_target_compile
}
...

>  My understanding is that with a "new enough" dejagnu, it won't be
> used -- so some users might still see the old behavior.
> 

AFAIU, yes. Hmm, that's not good.

> Basically gdb_default_target_compile is all a big monkeypatching hack

/me reads https://en.wikipedia.org/wiki/Monkey_patch

> and it would be way better to have some kind of more principled approach
> upstream.

Agreed.

> I don't know what that would look like.  And of course to get
> there we'd probably need even more monkeypatching.

The following uses the approach taken in lib/cell.exp.

Is this any better?

Thanks,
- Tom

diff --git a/gdb/testsuite/lib/ada.exp b/gdb/testsuite/lib/ada.exp
index 1345c747c5..6a3fd33240 100644
--- a/gdb/testsuite/lib/ada.exp
+++ b/gdb/testsuite/lib/ada.exp
@@ -19,11 +19,36 @@

 proc target_compile_ada_from_dir {builddir source dest type options} {
     set saved_cwd [pwd]
+
+    global board
+    set board [target_info name]
+    set save_multilib_flag [board_info $board multilib_flags]
+    set multilib_flag ""
+    foreach op $save_multilib_flag {
+       if { $op == "-pie" || $op == "-no-pie" } {
+           # Pretend gnatmake supports -pie/-no-pie, route it to
+           # linker.
+           append multilib_flag " -largs $op -margs"
+       } else {
+           append multilib_flag " $op"
+       }
+    }
+    if { $multilib_flag != "" } {
+       unset_board_info "multilib_flags"
+       set_board_info multilib_flags "$multilib_flag"
+    }
+
     catch {
         cd $builddir
         return [target_compile $source $dest $type $options]
     } result options
     cd $saved_cwd
+
+    if { $save_multilib_flag != "" } {
+       unset_board_info "multilib_flags"
+       set_board_info multilib_flags $save_multilib_flag
+    }
+
     return -options $options $result
 }