So I ran into a problem earlier - trying to allocate 2GB or more
on Windows would fail even if there was enough room. Mentioned it
in the D irc channel and a few fine folks pointed out that
Windows only allows 2GB for 32-bit applications unless you pass a
special flag which may or may not be a good idea.
I think to myself, "Easy solution, I'll just compile as 64-bit!"
But alas, my 64-bit executable suffers the same problem.
I boiled it down to a simple test:
void main()
{
import core.stdc.stdlib : malloc;
auto mem = malloc(2^^31);
assert(mem);
import core.stdc.stdio : getchar;
getchar();
}
I wrote this test with the C functions so that I can do a direct
comparison with a C program compiled with VS 2015:
#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
void *ptr = malloc((size_t)pow(2, 31));
assert(ptr);
getchar();
return 0;
}
I compile the D test with: `ldc2 -m64 -test.d`
I compile the C test with: `CL test.c`
`file` reports "PE32+ executable (console) x86-64, for MS
Windows" for both executables.
When the C executable runs, I see the allocation under "commit
change" in the Resource Monitor. When the D executable runs, the
assertion fails!
The D program is able to allocate up to 2^31 - 1 before failing.
And yes, I do have enough available memory to make a larger
allocation.
Can you help me solve this mystery?
