T070 tests portability

[J Farkas]

On 2016-01-05 at 17:41:06, David Bremner wrote:
> Tomi Ollila <tomi.ollila at iki.fi> writes:
> 
> > The page https://sourceware.org/gdb/onlinedocs/gdb/Returning.html
> > talks something about gdb not knowing the return type if function
> > was compiled without debug info... well, is this is the reason,
> > perhaps we should allow testing w/o debug info compiled in.
> 
> The test suite overall assumes debug info is present; T000-basic tests
> for this.

I'm not missing the debug infos (well, except for the thread library if I
understand correctly - and that affects a lot of other tests, but not this).
Perhaps it the version of gdb, but not any compilation flags that can be
changed for the notmuch tree.

Without the changes, I'm getting these two kind of errors (and as you can see,
the test for the debugging symbols passes too).

$ ./T000-basic.sh

T000-basic: Testing the test framework itself.
 PASS   success is reported like this
...
 PASS   PATH is set to build directory
 PASS   notmuch is compiled with debugging symbols
$ ./T070-insert.sh

T070-insert: Testing "notmuch insert"
 PASS   Insert zero-length file
...
 FAIL   Insert duplicate message
        --- T070-insert.6.expected      2016-01-06 13:31:01.644676102 +0000
        +++ T070-insert.6.output        2016-01-06 13:31:01.648675891 +0000
        @@ -1 +1 @@
        -2
        +      2
 PASS   Duplicate message does not change tags
 PASS   Insert message, add tag
...
 PASS   Tags starting with '-' in new.tags are forbidden
 PASS   Invalid tags set exit code
 FAIL   error exit when add_message returns OUT_OF_MEMORY
        --- T070-insert.26.expected     2016-01-06 13:31:06.940397013 +0000
        +++ T070-insert.26.output       2016-01-06 13:31:06.940397013 +0000
        @@ -1 +1 @@
        -1
        +255
warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.
index-file-OUT_OF_MEMORY.gdb:7: Error in sourced command file:
Return value type not available for selected stack frame.
Please use an explicit cast of the value to return.
 FAIL   success exit with --keep when add_message returns OUT_OF_MEMORY
...

(The above is then repeated for all gdb using `insert` tests.)

János