Re: [PATCH v4 10/15] explicitly test for stderr in gdb.base/dprintf.exp

[Andrew Burgess <aburgess@redhat.com>]

Bruno Larsen via Gdb-patches <gdb-patches@sourceware.org> writes:

> Not all compilers add stderr debug information when compiling a
> program. Clang, for instance, prefers to add nothing from standard
> libraries and let an external debug package have this information.
> Because of this, gdb.base/dprintf.exp was failing when GDB attempted to
> use dprintf as a call to fprintf(stderrr, ...), like this:
>
>  (gdb) PASS: gdb.base/dprintf.exp: call: fprintf: set dprintf style to call
>  continue
>  Continuing.
>  kickoff 1234
>  also to stderr 1234
>  'stderr' has unknown type; cast it to its declared type
>  (gdb) FAIL: gdb.base/dprintf.exp: call: fprintf: 1st dprintf (timeout)
>
> To avoid this false positive, we explicitly test to see if
> the compiler has added information about stderr at all, and abort
> testing dprintf as an fprintf call if it is unavailable.
> ---
>  gdb/testsuite/gdb.base/dprintf.exp | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/gdb/testsuite/gdb.base/dprintf.exp b/gdb/testsuite/gdb.base/dprintf.exp
> index 0b209c02a62..e214531f6dc 100644
> --- a/gdb/testsuite/gdb.base/dprintf.exp
> +++ b/gdb/testsuite/gdb.base/dprintf.exp
> @@ -111,6 +111,16 @@ proc test_call {} {
>  	test_dprintf "At foo entry.*arg=1235, g=2222\r\n" "2nd dprintf"
>      }
>  
> +    gdb_test_multiple "print stderr" "stderr symbol check" {
> +	-re "\\'stderr\\' has unknown type.*" {
> +	    untested "No information available for stderr, exiting early"
> +	    return
> +	}
> +	-re "\\\$1.*" {
> +	    pass "stderr is available"

I think this should be `pass $gdb_test_name`, but OK to commit with that
change.

Thanks,
Andrew

> +	}
> +    }
> +
>      with_test_prefix "fprintf" {
>  	restart
>  
> -- 
> 2.31.1