Manuel López-Ibáñez - PR30465 duplicated overflow warning (original) (raw)

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• From: "Manuel López-Ibáñez"
• To: gcc-patches
• Date: Wed, 17 Jan 2007 17:16:23 +0000
• Subject: PR30465 duplicated overflow warning

:ADDPATCH c/c++:

The current rationale for overflow warnings is that we don't emit a warning for the result of an operator is any of their operands has TREE_OVERFLOW set, since we assume that an overflow warning has already been given. This has been implemented for unary and binary operators, however, it hasn't been followed for the conversion operator. Hence, PR 30465.

If the expression to be converted has TREE_OVERFLOW set, we don't care about giving any other warnings for an overflow in conversion since the expression has already overflowed and a warning should have been given already for this expression.

Bootstrapped and regression tested with --enable-languages=all on i686-pc-linux-gnu.

OK for mainline?2007-01-18 Manuel Lopez-Ibanez manu@gcc.gnu.org

PR other/30465

• c-common.c (convert_and_check): Don't give warnings for conversion if 'expr' already overflowed.

testsuite/

PR other/30465

• gcc.dg/multiple-overflow-warn-3.c: New.
• g++.dg/warn/multiple-overflow-warn-3.C: New.

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