"pointer being freed was not allocated" error on Mac

[nnahito]

Thank you for the wonderful library.

I ran the following code on my Mac:

import uing
import strutils

var mEntry: MultilineEntry

proc extraction(_: Button) =
  echo repr(mEntry.text)

proc main = 
  let window = newWindow("Hello World!", 800, 600)

  mEntry = newMultilineEntry()

  let button = newButton("test", extraction)

  let hbox = newHorizontalBox(true)
  hbox.add(mEntry, true)
  hbox.add(button)


  window.child = hbox
  show window
  mainLoop()

init()
main()

It is a small program with Entry and buttons.
This code gets the value from Entry when the button is pressed.
At that time, the value is retrieved without any problem on Windows, but on a Mac, a memory error occurs.

malloc: *** error for object 0x10ccaa058: pointer being freed was not allocated
malloc: *** set a breakpoint in malloc_error_break to debug
SIGABRT: Abnormal termination.

Is it possible for you to correct this?
Thank you.

• MacOS 14.1.2（23B92）
  • Apple M1 Pro
  • 16 GB
• Nim Compiler Version 2.0.2 [MacOSX: amd64]
  • uing@0.8.0

[neroist]

Thank you for this issue, this is odd. Do the examples at https://github.com/libui-ng/libui-ng work for you?

[nnahito]

Thank you for your reply.
Sorry, what can I do with this link?
I would appreciate it if you could enlighten me!

[neroist]

Thank you for your reply. Sorry, what can I do with this link? I would appreciate it if you could enlighten me!

@nnahito Try building and running the libui examples; instructions are in the readme

[kai-odri]

Hi I am getting a similiar error on linux. It is only occurring when I call .text from Entry or Multiline entry.
e.g. nameEntry.text()
Im setting up my windows environment now to see if it works there.

The error message:

free(): invalid pointer
Traceback (most recent call last)
/home/kai/lightbringers/src/lightbringers.nim(126) lightbringers
/home/kai/lightbringers/src/lightbringers.nim(43) startApplication
/home/kai/.nimble/pkgs2/uing-0.8.1-92408d73d6e2e49e10c8d8d58aaaca63d0e85489/uing.nim(54) mainLoop
/home/kai/.nimble/pkgs2/uing-0.8.1-92408d73d6e2e49e10c8d8d58aaaca63d0e85489/uing.nim(80) wrapOnClick
/home/kai/lightbringers/src/insertdata_employee.nim :anonymous
/home/kai/.nimble/pkgs2/uing-0.8.1-92408d73d6e2e49e10c8d8d58aaaca63d0e85489/uing.nim(1470) text
/home/kai/.nimble/pkgs2/uing-0.8.1-92408d73d6e2e49e10c8d8d58aaaca63d0e85489/uing.nim free
SIGABRT: Abnormal termination.

OS: Arch Linux x86_64
PC: Latitude 7490 16GB
Kernel: 6.9.4-arch1-1
Nim: Nim Compiler Version 2.0.4

Edit: Runs fine on windows 10 with compiler v 2.0.6 with dynamic linking, static linking gives:

c:/users/kai/nim-2.0.6/dist/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: C:/Users/kai/nimcache/lightbringers_d/@mC@c@sUsers@skai@s.nimble@spkgs2@suing-0.8.1-92408d73d6e2e49e10c8d8d58aaaca63d0e85489@suing.nim.c.o:@mC@c@sUsers@skai@s.nimble@spkgs2@suing-0.8.1-92408d73d6e2e49e10c8d8d58aaaca63d0e85489@suing.nim.c:(.text+0x2fa0): undefined reference to `uiWindowOnPositionChanged'
collect2.exe: error: ld returned 1 exit status
Error: execution of an external program failed: 'C:\Users\kai\nim-2.0.6\dist\mingw64\bin\gcc.exe  @lightbringers_linkerArgs.txt'

Also quick question how would you go about implementing scrolling views?
Thanks, loving this library so far.

[neroist]

This is probably because the code frees result and not the returned cstring from the lower-level APIs...

[neroist]

@kai-odri @nnahito Do you mind testing now with the most recent commit?

[neroist]

Also quick question how would you go about implementing scrolling views?

I have no idea! libui-ng/libui-ng#281 & libui-ng/libui-ng#280 seem interesting, perhaps you could try combining those & wrapping uiScroll, uiNewScroll, and uiScrollSetChild.

[kai-odri]

Thankyou that works fine for me on linux now. Alright cheers I've had a look at that, I am not very experienced with Nim/C I'll see how I go.