------- Comment #7 from edwintorok at gmail dot com 2009-04-25 14:18 ------- (In reply to comment #5) > > > "An object shall have its stored value accessed only by an lvalue > > > expression > > > that has one of the following types: > > > > > > * a type compatible with the effective type of the object, > > > * a qualified version of a type compatible with the effective type of > > > the > > > object, > > > * a type that is the signed or unsigned type corresponding to the > > > effective > > > type of the object, > > > * a type that is the signed or unsigned type corresponding to a > > > qualified > > > version of the effective type of the object, > > > * an aggregate or union type that includes one of the aforementioned > > > types > > > among its members (including, recursively, a member of a subaggregate or > > > contained union), or > > > * a character type." > > > > > > I'm casting to a union that has both types as members, why doesn't that > > > fit > > > under the 5th case in the above quote? > > > > Because it is certainly backwards. > > Or rather, this refers to a compatible type to the type that was used > to store the value, so it doesn't apply to type-punning. >
Yes, the union has a compatibly type to the one used to store the value (it has a char member), hence the union can be used to access the value. I use a different member to access the value, but isn't that what unions are for? :) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39895
