id	summary	reporter	owner	description	type	status	priority	component	version	resolution	keywords	cc
189	Reference types allow unsound assignment	mlbrooks		"This code implies a reinterpret pointer cast.  But the code does not do a cast.
{{{
int main() {
    float x = 3.14;
    float & xx = x;
    int & yy = xx;  // not sound
    int y = yy;
    printf(""%d\n"", y);
}
}}}

Expected: Compiler error at ""not sound"" line, saying cannot initialize int & from float &.

Actual: Compiler success; program prints 1078523331 which is the decimal value of 0x4048f5c3, which is the IEEE 754 representation of 3.14.

Note that this unsoundness also happens at function return.

This allows for:
{{{
forall (dtype T, dtype S)
T & anycvt( S & s ) {
    return s; // not sound
}
int main() {
    float x = 3.14;
    int y = anycvt(x);
    printf(""%d\n"", y);
}
}}}

Expected: Compiler error at ""not sound"" line, saying cannot initialize T & from S &.

Actual: Compiler success; program prints 1078523331.
"	defect	new	major	cfa-cc	1.0