[Bug rtl-optimization/21402] wrong-code with inlining and type-punned pointer

[gdr at integrable-solutions dot net]

------- Additional Comments From gdr at integrable-solutions dot net  2005-05-21 21:42 -------
Subject: Re:  wrong-code with inlining and type-punned pointer

"schlie at comcast dot net" <gcc-bugzilla@gcc.gnu.org> writes:

| (In reply to comment #4)
| > Subject: Re:  wrong-code with inlining and type-punned pointer
| > Because this is what the standard says is allowed.  The standard also
| > says the comparisons and assignment between pointers without a case is
| > invalid code and should be diagnostic.  Again this is what the standard
| > says for these things and GCC follows the C standard.
| 
| Here's an interesting portion of the standard, which seems to direcly imply
| that signed and unsigned lvalue references are presumed to validly alias; so
| so this should place both in the same alias set, and potentially eliminate the
| default warning when comparing pointers which differ only in signness, as

Sorry, I don't see that implication.  However, GCC already has a
switch for tuning off such comparison.

-- Gaby


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21402