Re: Unexpected threads observed before main()
On Monday, 1 March 2021 at 06:50:42 UTC, rikki cattermole wrote: Do you still get them when you call your app like this? ./app --DRT-gcopt=parallel:0 Wow, Not getting with "--DRT-gcopt=parallel:0", Thanks a lot, didn't know GC had a parallel option that can be controlled(https://dlang.org/spec/garbage.html#gc_parallel). If possible, Can you also help me understand that why are the threads not despawned once the GC is done collecting in this example?
Re: Unexpected threads observed before main()
Do you still get them when you call your app like this? ./app --DRT-gcopt=parallel:0
Unexpected threads observed before main()
I had recently updated my dmd version to latest, i.e from 2.076.1
(I know, sorry) to 2.095.0 and suddenly my code has started
spawning extra threads which were not there before with no
obvious reasons, after trying to simplify and identify the cause
as much as possible, I have come up with this snippet of code:
module test;
// PART 1
class SomeClass
{
}
static this() // Works in both cases, "static this" as well as
"shared static this"
{
new SomeClass;
}
// PART 2
class TestThread
{
static this() // Works in both cases, "static this" as well
as "shared static this"
{
import core.memory;
GC.collect;
}
}
void main() // Voila! Extra 5 threads before starting main!
{
import std;
import core.thread;
auto pid = getpid;
// Linux hack to prevent having to do `top` and check num of
threads
writeln(" NumThreads: ", dirEntries("/proc/" ~ pid.to!string
~ "/task/", SpanMode.shallow).array.length);
// writeln("PID: ", pid, " NumThreads: ",
Thread.getAll.length); // This doesn't seem to give the right
number
while(true){}
}
This when running on my local Linux machine with dmd-2.095.0
shows that 6 threads are running but on running with dmd-2.076.1
(Sorry, haven't tried on all other dmds in between) gives only 1
thread. Something seems to be off here and to make it even more
confusing, when running this on run.dlang.io, it seems to only
give 1 thread. Is there something obviously wrong that I am doing
or this could be a potential bug in D runtime?
Re: Does reserve() preallocate for futher appends too?
On Monday, 1 March 2021 at 03:12:42 UTC, Adam D. Ruppe wrote: On Monday, 1 March 2021 at 03:07:19 UTC, Jack wrote: isn't clear for me if reserve() does preallocate memory so that that operator like arr ~= x can use previously allocate memory by reserve() or it's just used in slices like b = arr[x .. y]? Slicing never allocates memory. reserve extends the capacity for the ~= operator. thanks
Re: Does reserve() preallocate for futher appends too?
On Monday, 1 March 2021 at 03:07:19 UTC, Jack wrote: isn't clear for me if reserve() does preallocate memory so that that operator like arr ~= x can use previously allocate memory by reserve() or it's just used in slices like b = arr[x .. y]? Slicing never allocates memory. reserve extends the capacity for the ~= operator.
Does reserve() preallocate for futher appends too?
isn't clear for me if reserve() does preallocate memory so that that operator like arr ~= x can use previously allocate memory by reserve() or it's just used in slices like b = arr[x .. y]?
Re: How do I check if a type is assignable to null at compile time?
On Saturday, 27 February 2021 at 01:23:06 UTC, H. S. Teoh wrote:
On Sat, Feb 27, 2021 at 01:03:56AM +, Jack via
Digitalmars-d-learn wrote:
On Friday, 26 February 2021 at 23:37:18 UTC, Murilo wrote:
> On Friday, 26 February 2021 at 05:25:14 UTC, Jack wrote:
> > I started with:
> >
> > enum isAssignableNull(T) = is(T : Object) || isPointer(T);
> >
> > but how do I cover all cases?
>
> You can check if it's null with this `variable is null` and
> you can test it with assert as in `assert(variable is null);`
I mean a give type T not variablee
Why not just:
enum isAssignableNull(T) = is(typeof((T t){ t = null; }));
?
T
works too, thanks but I ended up using Nathan S. solution which
is quite fine too:
enum bool isAssignableNull(T) = is(typeof(null) : T);
Re: Name mangling problem with tiny Windows 10 load-time DLL example
On Sunday, 28 February 2021 at 22:10:21 UTC, Siemargl wrote: On Sunday, 28 February 2021 at 18:29:11 UTC, WhatMeWorry wrote: It seems pretty obvious the problem is with name mangling. But how to fix it? fixing int numb = 1; and your example work correct ldc 1.24 / win10 P.S.I'm not recommend using such keywords as 'file', may cross with other modules. I double checked my posting and of course works it now works!?!? I've been having trouble where it works and then it doesn't. I've been using examples with file.d, file1.d, file2.d, etc. I also came across the note that Windows file system is not case sensitive. Or is that case in-sensitive? This worked fine for Linux (Ubuntu) so you might be on to something.
Re: Name mangling problem with tiny Windows 10 load-time DLL example
On Sunday, 28 February 2021 at 18:29:11 UTC, WhatMeWorry wrote: It seems pretty obvious the problem is with name mangling. But how to fix it? fixing int numb = 1; and your example work correct ldc 1.24 / win10 P.S.I'm not recommend using such keywords as 'file', may cross with other modules.
Re: Name mangling problem with tiny Windows 10 load-time DLL example
mangleof should give _D4file6addOneFiZi, not _D6patron6addOneFiZi
Name mangling problem with tiny Windows 10 load-time DLL example
It seems pretty obvious the problem is with name mangling. But
how to fix it?
--
module file;
extern(D) export
{
int addOne(int i) { return (i + 1); }
}
--
module patron;
import file;
void main()
{
import std.stdio;
int n = 1;
writeln("mangled name of addOne is ", addOne.mangleof);
numb = addOne(numb);
}
--
ldc2 -m64 -c file.d
ldc2 -m64 -c patron.d
ldc2 -m64 -shared file.obj -ofloadTime.dll
Creating library loadTime.lib and object loadTime.exp
Both dumpbin /exports loadTime.lib and dumpbin /exports
loadTime.dll
shows: _D4file6addOneFiZi
ldc2 patron.obj loadTime.lib
patron.exe
mangled name of addOne is _D6patron6addOneFiZi
// and library function is never called. Does not abend though???
---
So the library function is named _D4file6addOneFiZi while the
user wants to call _D6patron6addOneFiZi
So which name is "correct" and how do I get them to agree with
each other?
Re: vibe.d selectively include attribute into tag using diet template
On 2/28/21 12:29 AM, JG wrote:
On Saturday, 27 February 2021 at 19:12:55 UTC, Steven Schveighoffer wrote:
If you use an expression without quotes
in diet, it becomes an interpolation.
Would you mind explaining in more detail what this means? How could one
use this, other than with booleans?
So if you have an expression as the right side of an attribute
assignment, it is treated as a D expression, which is then evaluated and
turned into string form.
So e.g. your original example:
tag(attribute='#{dexpression}')
can be written as:
tag(attribute=dexpression)
-Steve
Re: How can I make this work?
On Sunday, 28 February 2021 at 07:05:27 UTC, Jack wrote:
I'm using a windows callback function where the user-defined
value is passed thought a LPARAM argument type. I'd like to
pass my D array then access it from that callback function. How
is the casting from LPARAM to my type array done in that case?
The best way to do this is to put the array inside a struct and
pass the address of the struct instead. This way both length and
pointer are passed, and you have the option to add more things if
you ended up needing it later, and there's fewer weird things to
worry about.
int[] arr = [1, 2, 3];
struct MyMessage {
int[] arr;
}
// this far is easy enough
MyMessage* messagePointer = new MyMessage(arr);
// but we do need to tell the GC we intend to pass this to the
outside world
// failure to do this MIGHT lead to random crashes as the GC
can't see it (it can't look inside the Windows message queue),
assumes it is unused, and frees it out from under you.
import core.memory;
GC.addRoot(messagePointer);
// when the GC has a root, it will consider that pointer live
until further notice and not collect it nor its member variables.
// so it is now cool to do this
PostMessage(hwnd, MSG_WHATEVER, 0, cast(LPARAM) messagePointer);
/* then on the other side */
switch(iMsg) {
case MSG_WHATEVER:
MyMessage* messagePointer = cast(MyMessage*) lParam;
// need to tell the GC the pointer can be automatically
managed normally again. failure to do this will lead to a memory
leak
import core.memory;
GC.removeRoot(messagePointer);
// now can use it
foreach(item; messagePointer.arr) {
// yada yada yada
}
}
And it is the simplest thing, no missing length, no weird
property casting. The GC handled with two simple add/remove calls.
Re: dub git dependencies
On Sunday, 28 February 2021 at 11:11:27 UTC, bogdan wrote: Hi, I remember that I saw a while ago some PRs related to adding a git url for a dependency in the dub's package.json. I looked today in the docs and I can't find any info about this. What is the progress for this feature? Can we use it already? https://dub.pm/package-format-json.html#version-syntax Bogdan Yes, it is there, whether it is already documented somewhere I do not know. See an example here: https://github.com/dlang/dub/blob/05165362127aadad088fd178622c83c03393411b/test/git-dependency/dub.json Kind regards Andre
dub git dependencies
Hi, I remember that I saw a while ago some PRs related to adding a git url for a dependency in the dub's package.json. I looked today in the docs and I can't find any info about this. What is the progress for this feature? Can we use it already? https://dub.pm/package-format-json.html#version-syntax Bogdan
Re: How can I make this work?
On 28/02/2021 11:05 PM, Max Haughton wrote: Do the windows APIs expect the length in memory rather than as a parameter? This sounds like its being sent via a user field to be passed to a callback. I.e. event loop for a window. In this sort of case you only get one parameter on the callback and it is only big enough for a pointer.
Re: How can I make this work?
On Sunday, 28 February 2021 at 09:18:56 UTC, Rumbu wrote: On Sunday, 28 February 2021 at 09:04:49 UTC, Rumbu wrote: On Sunday, 28 February 2021 at 07:05:27 UTC, Jack wrote: I'm using a windows callback function where the user-defined value is passed thought a LPARAM argument type. I'd like to pass my D array then access it from that callback function. How is the casting from LPARAM to my type array done in that case? for example, I need something like this to work: int[] arr = [1, 2, 3]; long l = cast(long) cast(void*) arr.ptr; int[] a = cast(int[]) cast(void*) l; LPARAM is not long on 32 bits, it's int. Use LPARAM instead of long. And you are passing only the address of the first element this way, loosing the array/slice length. This should work, but keep in mind that you have no warranty that the array stays in memory and it is not garbage collected. int[] arr = [1, 2, 3]; LPARAM l = cast(LPARAM)cast(void*) int[] a = *cast(int[]*)(cast(void*)l); Do the windows APIs expect the length in memory rather than as a parameter? Also Rumbu can you check your email - I may have emailed you on an old email address by accident, but it's about the blog and it will be from mh240@...
Re: How can I make this work?
On Sunday, 28 February 2021 at 09:04:49 UTC, Rumbu wrote: On Sunday, 28 February 2021 at 07:05:27 UTC, Jack wrote: I'm using a windows callback function where the user-defined value is passed thought a LPARAM argument type. I'd like to pass my D array then access it from that callback function. How is the casting from LPARAM to my type array done in that case? for example, I need something like this to work: int[] arr = [1, 2, 3]; long l = cast(long) cast(void*) arr.ptr; int[] a = cast(int[]) cast(void*) l; LPARAM is not long on 32 bits, it's int. Use LPARAM instead of long. And you are passing only the address of the first element this way, loosing the array/slice length. This should work, but keep in mind that you have no warranty that the array stays in memory and it is not garbage collected. int[] arr = [1, 2, 3]; LPARAM l = cast(LPARAM)cast(void*) int[] a = *cast(int[]*)(cast(void*)l);
Re: How can I make this work?
On Sunday, 28 February 2021 at 07:05:27 UTC, Jack wrote: I'm using a windows callback function where the user-defined value is passed thought a LPARAM argument type. I'd like to pass my D array then access it from that callback function. How is the casting from LPARAM to my type array done in that case? for example, I need something like this to work: int[] arr = [1, 2, 3]; long l = cast(long) cast(void*) arr.ptr; int[] a = cast(int[]) cast(void*) l; LPARAM is not long on 32 bits, it's int. Use LPARAM instead of long.
Re: How can I make this work?
On 28/02/2021 8:05 PM, Jack wrote: int[] arr = [1, 2, 3]; size_t l = cast(size_t)arr.ptr; Okay, so far so good int[] a = cast(int[]) cast(void*) l; Umm, you haven't specified a length? int[] a = (cast(int*)l)[0 .. 3]; If the callback is being called (in effect under the current stack frame and won't escape), I would wrap the data you need in a struct and pass that to it instead by pointer. No need for heap allocation and gives a way to pass more complex data should the need arise.
