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digitalmars.D.learn - Weird array setting behaviour on Windows(-m64)

reply ref2401 <refactor24 gmail.com> writes:
Hello,

I got stuck with a weird array setting behaviour and I need help. 
Just have a look at the example.

OS: Win 8.1 Pro
DMD: v2.071.0
Build-cmd: dmd main.d -ofconsole-app.exe -debug -unittest -g -wi 
-m64

module dmain;
import std.stdio;

struct Vec {
	float a;
}

void main(string[] args) {
	Vec[] array = new Vec[4];

	writeln("before: ", array); //  prints [Vec(nan), Vec(nan), 
Vec(nan), Vec(nan)]
	
	array[] = Vec(24);

	writeln("after: ", array); // prints [Vec(0), Vec(0), Vec(0), 
Vec(0)]
}

Seems like slicing is broken in general. All the following 
variations produce different results but they are all wrong.
array[] = Vec(24);
array[0 .. 1] = Vec(24);
array[0 .. $] = Vec(24);

It works as expected if I do one of the following things:
1. Get rid of -m64. If I compile with -m32 flag then I cannot 
replicate the issue.

2. Changing the type of the Vec.a field from float to real, int, 
uint, long, ulong fixes the issue. Double still causes the issues.

3. Adding new fields to the Vec struct.

3.1. Vec {float a, b; } still does not work but the result is 
slightly different.
array[] = Vec(24, 5);
writeln("after: ", array); // [Vec(5, 0), Vec(5, 0), Vec(5, 0), 
Vec(5, 0)]

3.2. Vec { float a, b, c; } works fine.

4. Using index operator: array[0] = Vec(24) works fine
Apr 13 2016
parent reply rikki cattermole <rikki cattermole.co.nz> writes:
On 14/04/2016 2:49 AM, ref2401 wrote:

 Hello,

 I got stuck with a weird array setting behaviour and I need help. Just
 have a look at the example.

 OS: Win 8.1 Pro
 DMD: v2.071.0
 Build-cmd: dmd main.d -ofconsole-app.exe -debug -unittest -g -wi -m64

 module dmain;
 import std.stdio;

 struct Vec {
      float a;
 }

 void main(string[] args) {
      Vec[] array = new Vec[4];

      writeln("before: ", array); //  prints [Vec(nan), Vec(nan),
 Vec(nan), Vec(nan)]

      array[] = Vec(24);

      writeln("after: ", array); // prints [Vec(0), Vec(0), Vec(0), Vec(0)]
 }

 Seems like slicing is broken in general. All the following variations
 produce different results but they are all wrong.
 array[] = Vec(24);
 array[0 .. 1] = Vec(24);
 array[0 .. $] = Vec(24);

 It works as expected if I do one of the following things:
 1. Get rid of -m64. If I compile with -m32 flag then I cannot replicate
 the issue.

 2. Changing the type of the Vec.a field from float to real, int, uint,
 long, ulong fixes the issue. Double still causes the issues.

 3. Adding new fields to the Vec struct.

 3.1. Vec {float a, b; } still does not work but the result is slightly
 different.
 array[] = Vec(24, 5);
 writeln("after: ", array); // [Vec(5, 0), Vec(5, 0), Vec(5, 0), Vec(5, 0)]

 3.2. Vec { float a, b, c; } works fine.

 4. Using index operator: array[0] = Vec(24) works fine


Verified that it is a codegen problem for Win64 and not *nix.
Please file a bug report.
Apr 13 2016
parent ref2401 <refactor24 gmail.com> writes:
On Wednesday, 13 April 2016 at 15:07:09 UTC, rikki cattermole 
wrote:


 Verified that it is a codegen problem for Win64 and not *nix.
 Please file a bug report.


https://issues.dlang.org/show_bug.cgi?id=15921
Done, Thanks
Apr 13 2016