Hello,

I'm trying to use setjmp and longjmp on Windows with DMD compiler (version 2.064). When compiled as 64-bit application, it works, but 32-bit version crashes inside longjmp. What should be changed to get it to work?

I tried changing value of _JBLEN for x86 to some bigger number (like 1024), but it crashes too.

Code:

import std.stdio;

version(Windows)
{
	version(X86)
		enum _JBLEN = 64;
	else version(X86_64)
		enum _JBLEN = 256;
	else version(IA64)
		enum _JBLEN = 528;
	
	alias ubyte[_JBLEN] jmp_buf;

	extern(C)
	{
		int _setjmp(ref jmp_buf _Buf);
		void longjmp(ref jmp_buf _Buf, int _Value);
	}
	
	alias _setjmp setjmp;
}

void main()
{
	jmp_buf env;
	uint i;
	if(setjmp(env) < 3)
	{
		writeln("ping");
		longjmp(env, ++i);
	}
	writeln("done");
}

Call stack:

c:\Users\vbox\Documents\test>test.exe
ping
object.Error: Access Violation
----------------
0x00423F78 in _local_unwind
0x004214D0 in longjmp
0x0040B300 in void rt.dmain2._d_run_main(int, char**, extern (C) int function(char[][])*).runAll().void __lambda1()
0x0040B2D3 in void rt.dmain2._d_run_main(int, char**, extern (C) int function(char[][])*).runAll()
0x0040B1EB in _d_run_main
0x0040B018 in main
0x0042142D in mainCRTStartup
0x754F3677 in BaseThreadInitThunk
0x77959F42 in RtlInitializeExceptionChain
0x77959F15 in RtlInitializeExceptionChain
----------------

On Saturday, 16 November 2013 at 14:14:24 UTC, Piotr Podsiadły wrote:
> Hello,
>
> I'm trying to use setjmp and longjmp on Windows with DMD compiler (version 2.064). When compiled as 64-bit application, it works, but 32-bit version crashes inside longjmp. What should be changed to get it to work?
>
> I tried changing value of _JBLEN for x86 to some bigger number (like 1024), but it crashes too.
>
> Code:
>
> import std.stdio;
>
> version(Windows)
> {
> 	version(X86)
> 		enum _JBLEN = 64;
> 	else version(X86_64)
> 		enum _JBLEN = 256;
> 	else version(IA64)
> 		enum _JBLEN = 528;
> 	
> 	alias ubyte[_JBLEN] jmp_buf;
>
> 	extern(C)
> 	{
> 		int _setjmp(ref jmp_buf _Buf);
> 		void longjmp(ref jmp_buf _Buf, int _Value);
> 	}
> 	
> 	alias _setjmp setjmp;
> }

What kind of problem you try to solve by manual defining system data structures? Why not use platform independent valid declarations? Why did you decide that _JBLEN is 64, 256, 528 according to version? Why did you decide that having _JBLEN bytes filled with zeros is a valid value of jmp_buf object? Why should setjmp/longjmp take buffer by reference?

> void main()
> {
> 	jmp_buf env;
> 	uint i;
> 	if(setjmp(env) < 3)
> 	{
> 		writeln("ping");
> 		longjmp(env, ++i);
> 	}
> 	writeln("done");
> }
>
> Call stack:
>
> c:\Users\vbox\Documents\test>test.exe
> ping
> object.Error: Access Violation
> ----------------
> 0x00423F78 in _local_unwind
> 0x004214D0 in longjmp
> 0x0040B300 in void rt.dmain2._d_run_main(int, char**, extern (C) int function(char[][])*).runAll().void __lambda1()
> 0x0040B2D3 in void rt.dmain2._d_run_main(int, char**, extern (C) int function(char[][])*).runAll()
> 0x0040B1EB in _d_run_main
> 0x0040B018 in main
> 0x0042142D in mainCRTStartup
> 0x754F3677 in BaseThreadInitThunk
> 0x77959F42 in RtlInitializeExceptionChain
> 0x77959F15 in RtlInitializeExceptionChain
> ----------------

Try to use proper version of setjmp/jmp_buf from druntime.
By the way, why did you decide to use it in D language in a first place?

On Saturday, 16 November 2013 at 14:41:46 UTC, Maxim Fomin wrote:
> What kind of problem you try to solve by manual defining system data structures? Why not use platform independent valid declarations? Why did you decide that _JBLEN is 64, 256, 528 according to version? Why did you decide that having _JBLEN bytes filled with zeros is a valid value of jmp_buf object? Why should setjmp/longjmp take buffer by reference?

I couldn't find these declarations for Windows in druntime (there is only POSIX version).
Values of _JBLEN are based on constants from headers from DMC (x86 version) and Visual Studio (x86_64 and ia64).

These are declarations copied from setjmp.h from DMC:

#define _JBLEN 16
typedef int jmp_buf[_JBLEN];

#define __CLIB	__cdecl
int __CLIB _setjmp(jmp_buf);
void __CLIB longjmp(jmp_buf,int);

jmp_buf is initialized by the first call to setjmp, so its initial value doesn't matter.
In C, arrays are alawys passed as a pointer - that's why I used ref.

> Try to use proper version of setjmp/jmp_buf from druntime.
> By the way, why did you decide to use it in D language in a first place?

I'm trying to use libpng and libjpeg directly from D, without any wrappers.
These libraries use longjmp to handle errors (the only alternative is to call exit() or abort()).

On Saturday, 16 November 2013 at 16:22:17 UTC, Piotr Podsiadły wrote:
> On Saturday, 16 November 2013 at 14:41:46 UTC, Maxim Fomin wrote:
>> What kind of problem you try to solve by manual defining system data structures? Why not use platform independent valid declarations? Why did you decide that _JBLEN is 64, 256, 528 according to version? Why did you decide that having _JBLEN bytes filled with zeros is a valid value of jmp_buf object? Why should setjmp/longjmp take buffer by reference?
>
> I couldn't find these declarations for Windows in druntime (there is only POSIX version).
> Values of _JBLEN are based on constants from headers from DMC (x86 version) and Visual Studio (x86_64 and ia64).
>
> These are declarations copied from setjmp.h from DMC:
>
> #define _JBLEN 16
> typedef int jmp_buf[_JBLEN];
>
> #define __CLIB	__cdecl
> int __CLIB _setjmp(jmp_buf);
> void __CLIB longjmp(jmp_buf,int);
>
> jmp_buf is initialized by the first call to setjmp, so its initial value doesn't matter.
> In C, arrays are alawys passed as a pointer - that's why I used ref.
>
>> Try to use proper version of setjmp/jmp_buf from druntime.
>> By the way, why did you decide to use it in D language in a first place?
>
> I'm trying to use libpng and libjpeg directly from D, without any wrappers.
> These libraries use longjmp to handle errors (the only alternative is to call exit() or abort()).

As an alternative to those libraries, may I suggest using the DevIL binding in Derelict? It's quite easy to use:

https://github.com/aldacron/Derelict3

Le 16/11/2013 23:26, Rene Zwanenburg a écrit :
> On Saturday, 16 November 2013 at 16:22:17 UTC, Piotr Podsiadły wrote:
>> On Saturday, 16 November 2013 at 14:41:46 UTC, Maxim Fomin wrote:
>>> What kind of problem you try to solve by manual defining system data
>>> structures? Why not use platform independent valid declarations? Why
>>> did you decide that _JBLEN is 64, 256, 528 according to version? Why
>>> did you decide that having _JBLEN bytes filled with zeros is a valid
>>> value of jmp_buf object? Why should setjmp/longjmp take buffer by
>>> reference?
>>
>> I couldn't find these declarations for Windows in druntime (there is
>> only POSIX version).
>> Values of _JBLEN are based on constants from headers from DMC (x86
>> version) and Visual Studio (x86_64 and ia64).
>>
>> These are declarations copied from setjmp.h from DMC:
>>
>> #define _JBLEN 16
>> typedef int jmp_buf[_JBLEN];
>>
>> #define __CLIB    __cdecl
>> int __CLIB _setjmp(jmp_buf);
>> void __CLIB longjmp(jmp_buf,int);
>>
>> jmp_buf is initialized by the first call to setjmp, so its initial
>> value doesn't matter.
>> In C, arrays are alawys passed as a pointer - that's why I used ref.
>>
>>> Try to use proper version of setjmp/jmp_buf from druntime.
>>> By the way, why did you decide to use it in D language in a first place?
>>
>> I'm trying to use libpng and libjpeg directly from D, without any
>> wrappers.
>> These libraries use longjmp to handle errors (the only alternative is
>> to call exit() or abort()).
>
> As an alternative to those libraries, may I suggest using the DevIL
> binding in Derelict? It's quite easy to use:
>
> https://github.com/aldacron/Derelict3

Piotr Podsiadły help us to remove SDL_Image from DQuick. Our goal is to avoid big dependencies, to provide a light weight and easy to build/install library.
An other point is to simplify port to new platforms such as Smartphones OS, or any other embedded devices, video games consoles,...

It's important for "D" to support this kind of feature correctly.