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If I allocate a fixed string, do I also need to perform bounds checking to ensure that assignments to that string do not exceed beyond its boundaries? I'm hesitant to say "yes", but I would like a official response. Are there any edge cases which I should be aware of?

See this example where I write ...

Alternatively, you can define #PB_ListIcon_Unchecked yourself in the meantime instead of comparing with 0.

... such conditions are bound to happen because the thread is still accessing resources that the main program is in the process of cleaning up.

In your case the crash is probably happening because the PB memory heap has already been destroyed when the AllocateMemory() call happens.

If this is ...

I'm experiencing intermittent [ERROR] Invalid memory access errors (read error at a random address) at an AllocateMemory() after a program has reached the end (no End keyboard; the program simply reaches the end of the main source file).

The access error is inconsistent on each run but appears to ...

PureBasic 5.73 x86 on Windows 10.

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Error
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An Error has been detected in the IDE!

Error: Invalid memory access



IDE build on 11/23/2020 [10:16] by Fred

Branch: master Revision: 79192e40282a
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OK ...

WM_MOUSELAST identifies the last mouse-related constant between it and WM_MOUSEFIRST. As new constants were added this number was expanded. It corresponds with the features configured by the Win32 SDK. So it will always return the correct constant for what is defined but in the case of PureBasic you ...

WM_MOUSELAST is defined as 0x0209 but has been at least 0x020a since Windows 98. Its current value is 0x020e.

#if _WIN32_WINNT >= 0x0600
#define WM_MOUSELAST 0x020e
#elif _WIN32_WINNT >= 0x0500
#define WM_MOUSELAST 0x020d
#elif (_WIN32_WINNT >= 0x0400) || (_WIN32_WINDOWS > 0x0400)
#define WM ...

WM_CLIPBOARDUPDATE 0x031D
WM_DWMCOLORIZATIONCOLORCHANGED 0x0320
WM_DWMCOMPOSITIONCHANGED 0x031e
WM_DWMNCRENDERINGCHANGED 0x031f
WM_DWMSENDICONICLIVEPREVIEWBITMAP 0x0326
WM_DWMSENDICONICTHUMBNAIL 0x0323
WM_DWMWINDOWMAXIMIZEDCHANGE 0x0321
WM_GETTITLEBARINFOEX 0x033F
WM_INPUT_DEVICE_CHANGE 0x00FE
WM ...

Tested with the latest PureBasic 5.73. I was experimenting with threads when I spotted this.

The PureBasic application will continue to consume memory until it crashes:

Procedure.s FuncStaticString()
Static string.s

string.s=LSet("",32,Chr(97+Random(25,0)))
EndProcedure

Procedure ThreadTest ...

You're right. I see the memory allocation when I enable "Committed Size" in Task Manager.

It's odd how performance differs when allocating IDs incrementally vs decrementally. I also wonder what PureBasic is doing as it closes that causes the operating system to allocate memory. It shouldn't need to ...

:| :| :| :|

Alright. That makes a lot of sense.

I still don't expect it to crash as a result, which it not a result of disabling the debugger but by how these functions handle being fed large numbers. The only reason I disabled the debugger at all was because of the warning which, as we've found ...

What does the title say?

Invalid memory access on DisableDebugger line when using very large numbers with CreateImage

This is a bug.

Why do you think it's OK for the debugger point you to a completely different line than where the problem occurred?

Demivec found where this is defined is in the documentation:

The static, indexed way, allows you to reference an object by a predefined numeric value. The first available index number is 0 and subsequent indexes are allocated sequentially. This means that if you use the number 0 and then the ...

Case closed.


No, it's not. What does the title of the topic say?

Thanks, Demivec. This was very helpful and informative. I was looking at "Handles and Numbers" in the documentation and didn't see the page you referenced.

This worked without issue in PureBasic (x86) but this may have been luck.

It's called a hash or tree map. One has O(n) lookup and the other is O(logn). Either one would be just as fast as a static lookup table on modern computers, would use a tiny fraction of memory, and would be immune to this problem entirely.

A static array is not the only way to store a lookup table.