Re: [rfa/doco] PROBLEMS: add regressions since gdb 6.0

[David Carlton <carlton@kealia.com>]

On Wed, 17 Mar 2004 13:55:28 -0500 (EST), mec.gnu@mindspring.com (Michael Elizabeth Chastain) said:

mec> gdb/826: variables in C++ namespaces have to be enclosed in quotes
mec> 
mec> When referring to a variable in C++ code that is inside a
mec> namespace, you have to put it inside single quotes.

dc> This is only true in rare circumstances, and it was always true in
dc> versions before 6.1!  So whatever it might be, it's not a regression.
dc> (Hmm: I should probably close that bug report, since it should largely
dc> be fixed by now.)

> This test case works with gdb 6.0 and it does not work with gdb
> gdb-6_1-branch.

>   # gdb 6.0, gcc 3.3.3, -gstabs+
>   (gdb) print (ClassWithEnum::PrivEnum) 42
>   $26 = yellow
>   PASS: gdb.cp/classes.exp: print (ClassWithEnum::PrivEnum) 42

>   # gdb gdb-6_1-branch, gcc 3.3.3, -gstabs+
>   (gdb) print (ClassWithEnum::PrivEnum) 42
>   A syntax error in expression, near `42'.
>   KFAIL: gdb.cp/classes.exp: print (ClassWithEnum::PrivEnum) 42 (PRMS: gdb/826)

> Actually, the word 'variable' is funny, because
> ClassWithEnum::PrivEnum is a type, not a variable.  But that's what
> the test script calls this problem.  And it's definitely a
> regression.

I don't think that looking for KFAILs is a good way to identify
whether or not a specific PR is a regression.  In this particular
instance, if you go to your table comparing 6.0 suite HEAD to 6.1
suite HEAD and, for example, look at the third column (GCC 3.3.3,
DWARF-2), you'll see a whole bunch of FAIL=>PASS transitions.  And a
_lot_ of them have to do with this bug being fixed: this is fairly
obvious in situations where, with GCC 6.0, "print 'AAA::c'" passes but
"print AAA::c" fails, but there are also examples further down where
there is no test using single quotes and where, if you did use single
quotes, you'd get unexpected output.

So I think the testsuite regression=>PR+description transition should
involve some more steps - the corresponding PR may be much broader
than the particular testsuite regression, and some of those broader
areas may involve situations where GDB has improved rather than
regressed.

David Carlton
carlton@kealia.com