[PATCH] Fix PR39246: -Wuninitialized for partially initialized complex

[Thomas Preud'homme]

Hi Richard,

> From: Richard Biener [mailto:richard.guenther@gmail.com]
> >
> > The ChangeLog are as follows:
> >
> > *** gcc/ChangeLog ***
> >
> > 2014-05-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>
> >
> >         PR middle-end/39246
> >         * tree-complex.c (expand_complex_move): Keep line info when
> expanding
> >         complex move.
> 
> This part and the corresponding testcase adjustment is ok.  You can
> commit it separately.

Only the change to tree-complex.c should be commited then, as it just changes
the location for target where the test was failing to the return line.

The current situation for uninit-13.c is:

					Warning location
Target return complex in register(s)	partial init
Target return complex on the stack	declaration

With the change to tree-complex.c the situation for the same test becomes:

					Warning location
Target return complex in register(s)	partial init
Target return complex on the stack	return

So either I don't touch the test or I move it to the return but I will just change
the set of target for which this test fails in doing so.

> 
> >         * tree-ssa-uninit.c (warn_uninit): New argument. Ignore assignment of
> >         complex expression. Use new argument to display correct location for
> >         values coming from phi statement.
> >         (warn_uninitialized_vars): Adapt to new signature of warn_uninit.
> >         (warn_uninitialized_phi): Pass location of phi argument to warn_uninit.
> >         * tree-ssa.c (ssa_undefined_value_p): For SSA_NAME initialized by a
> >         COMPLEX_EXPR, recurse on each part of the COMPLEX_EXPR.
> 
> This change will also affect PRE in a bogus way.  It also affects
> tree-complex.c lowering process, eventually in a similar pessimizing way.
> 
> So please do the change local to tree-ssa-uninit.c.

Done, see attached patch.

Best regards,

Thomas
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