Hello,
I casually found a bug in the current released GCC 4.0.0. However, I
have located the wrong code, and it's very easy to be fixed, so it's not
necessary to still submit a bug report. See the following artificial
C++ code:
int *x;
void f()
{
do
{
const int *&rx = (const int*&)(x);
rx = 0;
}while( *x );
}
Compile it with command "cc1plus -O2" will cause an internal error
happening in get_indirectref_operands, at tree-ssa-operands.c:1449,
which is because GCC gets into the unreachable branch. The underlying
fault is in create_expression_by_pieces, at tree-ssa-pre.c:1382.
if (!is_gimple_min_invariant (genop1))
newexpr = force_gimple_operand (folded, &forced_stmts, false,
NULL);
else
1382: newexpr = genop1;
I guess it's a clerical error. The genop1 is just a GIMPLE
min_invariant operand of the expression being processed. What holds the
needed expression here is the variable FOLDED, so this line should be as
following.
1382: newexpr = folded;
I modified it as so and it works correctly when compiling the above
artificial code and also my project files on which the unmodified
version fails.
I hope this is helpful to the maintainers.
