Float to string causes SIGSEGV with --hotcodereloading:on

[stisa]

Converting a float to string causes a crash at runtime with --hotcodereloading:on.

Example

# logic.nim
proc logic*() =
  echo 4.21  # this works
  var x = 12.4
  echo x # this crashes
logic()

compile and run with:

nim c -r --hotcodereloading:on logic.nim

This will crash with SIGSEGV: Illegal storage access. at strmantle.nim(94) addFloat

Current Output

Hint: used config file 'C:\Dev\nim-git\config\nim.cfg' [Conf]
Hint: used config file 'C:\Dev\nim-git\config\config.nims' [Conf]
....
Hint: 21871 lines; 0.361s; 20.5MiB peakmem; Debug build; 
proj: C:\Users\stisa\OneDrive\Progetti\hcr\logic.nim; out: C:\Users\stisa\OneDrive\Progetti\hcr\logic.exe [SuccessX]
Hint: C:\Users\stisa\OneDrive\Progetti\hcr\logic.exe  [Exec]
4.21
Traceback (most recent call last)
C:\Users\stisa\OneDrive\Progetti\hcr\logic.nim(6) logic
C:\Users\stisa\OneDrive\Progetti\hcr\logic.nim(4) logic
C:\Dev\nim-git\lib\system\strmantle.nim(99) nimFloatToStr
C:\Dev\nim-git\lib\system\strmantle.nim(94) addFloat
SIGSEGV: Illegal storage access. (Attempt to read from nil?)
Error: execution of an external program failed: 'C:\Users\stisa\OneDrive\Progetti\hcr\logic.exe '

Expected Output

4.21
12.4

Additional Information

Compiler version (nim -v):

Compiled at 2020-07-23
Copyright (c) 2006-2020 by Andreas Rumpf

git hash: 925dd92e07bd8b031c9f237ceb9e352c34a97d64
active boot switches: -d:release

Discovered this when working on the hcr branch of jupyternim (here)

[stisa]

May be linked to #11974 ?

[stisa]

More info and possible workaround: moving writeFloatToBuffer from formatfloat.nim to strmantle (exporting the other two procs and using from formatfloat import nil to avoid some ambiguous calls) seems enough to fix this.

[darthdeus]

I just tested this on Linux and it seems to work without any issues

[pipik] ~/projects/nimtest/bug !dot!
$ LD_LIBRARY_PATH=. nim c -r --hotcodereloading:on logic.nim
Hint: used config file '/home/darth/.choosenim/toolchains/nim-1.6.8/config/nim.cfg' [Conf]
Hint: used config file '/home/darth/.choosenim/toolchains/nim-1.6.8/config/config.nims' [Conf]
.........................................................
Hint: gc: refc; opt: none (DEBUG BUILD, `-d:release` generates faster code)
26696 lines; 0.131s; 25.523MiB peakmem; proj: /home/darth/projects/nimtest/bug/logic.nim; out: /home/darth/projects/nimtest/bug/logic [SuccessX]
Hint: /home/darth/projects/nimtest/bug/logic  [Exec]
4.21
12.4

Using latest stable

$ nim -v
Nim Compiler Version 1.6.8 [Linux: amd64]
Compiled at 2022-09-27
Copyright (c) 2006-2021 by Andreas Rumpf

git hash: c9f46ca8c9eeca8b5f68591b1abe14b962f80a4c
active boot switches: -d:release

Maybe the bug is Windows only?

[stisa]

Might be, or it was fixed as a side effect of something else. I'll try it out on my machine and report back