Bug 1254 – Using a parameter initialized to void in a compile-time evaluated function doesn't work

int foo() { int x = void; return bar(x); } int bar(int dummy) { return 1; } const i = foo(); The above results in "Error: variable x is used before initialization" without a file name or line number. The Functions page at http://www.digitalmars.com/d/function.html says only that use of uninitialized variables can give different results at compile time, but it doesn't disallow it. There are two bugs: first, the error message should have a file name and line number, and second, there should be no error message and the code should compile.

The compiler is allowed to issue errors for "use before initialized" problems, although it is not required to detect them. On a pragmatic note, I can't see anything good coming from supporting using the values of uninitialized variables in CTFE. The error message missing file/line info is still a bug, though.

Well, there's no particular use for it in CTFE, but the thing is that a function may be used both with and without CTFE. In the latter case, not initializing a variable is an optimization (though in this case of a single integer it hardly matters), and may be useful. In the CTFE case, it might as well be initialized anyway, if that's easier: it's a bug to rely on the contents of uninitialized variables anyway.

The error message should have the file/line. But the code is erroneous - even though the uninitialized value is eventually unused, it is technically used when passed to bar(), and hence is illegal.

Error message has a line number in DMD 1.017. Marking as FIXED, as it seems that's all I'll get.