Bug 4199 – D2 core.sys.posix.*: array parameters of C functions must be ref
Status
RESOLVED
Resolution
DUPLICATE
Severity
normal
Priority
P2
Component
druntime
Product
D
Version
D2
Platform
All
OS
All
Creation time
2010-05-17T00:41:00Z
Last change time
2014-02-15T02:42:29Z
Assigned to
sean
Creator
rsinfu
Comments
Comment #0 by rsinfu — 2010-05-17T00:41:40Z
This program core dumps on FreeBSD (and it should on Linux):
--------------------
import core.sys.posix.setjmp;
void main()
{
jmp_buf st = void;
setjmp(st);
assert(0); // trap; not reached due to the bug
}
--------------------
The C standard defines jmp_buf as an array. In C and D1, the definition works since arrays (static arrays) are passed to functions by reference. But in D2, static arrays are passed by value! Hence the above program core dumps.
So, setjmp() and longjmp() must be declared as:
--------------------
int setjmp(ref jmp_buf);
void longjmp(ref jmp_buf, int);
--------------------
Comment #1 by rsinfu — 2010-05-17T06:17:01Z
Hmm, the problem seems more generic. More functions in core.sys.posix.* take array parameters, and these are not ref-ed. A good example is pipe():
--------------------
import std.stdio;
import core.sys.posix.unistd; // int pipe(int[2]);
void main() {
int[2] pp;
pipe(pp);
writeln("Hello, world."); // not reached!
}
--------------------
The pipe() must be declared like: int pipe(ref int[2]).
Comment #2 by schveiguy — 2010-05-17T06:34:35Z
*** This issue has been marked as a duplicate of issue 3604 ***