ref https://github.com/nim-lang/Nim/pull/24686
With this PR
```nim
import std/streams
proc foo() =
var name = newStringStream("2r2")
raise newException(ValueError, "sh")
try:
foo()
except:
discard
echo 123
```
this example no longer leaks
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
(cherry picked from commit 510ac84518)
Lets single threaded applications benefit from tracking foreign cells as
well.
After this, `SmallChunk` technically doesn't need to act as a linked
list anymore I think, gotta investigate that more though.
The likelihood of overflowing `chunk.free` also rises, so to work around
that it might make sense to check `foreignCells` instead of adjusting
free space or replace free with a counter for the local capacity.
For Nim compile I can observe a ~10mb reduction, and smaller ones for
other projects.
(cherry picked from commit 881fbb8f81)
Ref: https://github.com/nim-lang/Nim/issues/23788
There was a small leak in the above issue even after fixing the
segfault. The sizes of `free` and `acc` were changed to 32bit because
adding the `foreignCells` field will drastically increase the memory
usage for programs that hold onto memory for a long time if they stay as
64bit.
(cherry picked from commit fd1e62a7e2)
I have made `realloc` absorb unused adjacent memory, which improves the
performance. I'm investigating whether `deallocOsPages` can be used to
improve memory comsumption.
(cherry picked from commit 53855a9fa3)
fixes#23742
Before my PR, `setLen(0)` doesn't free buffer if `s != nil`, but it
allocated unnecessary memory for `strs`. This PR rectifies this
behavior. `setLen(0)` no longer allocates memory for uninitialized
strs/seqs
(cherry picked from commit 2bef08774f)
Per manual, `panics:on` affects _only_ `Defect`:s - thus `sysFatal`
should not redirect any other exceptions.
Also, when `sysFatal` is used in `nimPanics` mode, it should use regular
exception handling pipeline to ensure exception hooks are called
consistently for all raised defects.
(cherry picked from commit 58c44312af)
`{.push overflowChecks: off.}` works in backends. Though it could be
implemented as a magic function.
By inspecting the generated C code, the overflow check is eliminated in
the debug or release mode.
Likewise, the index checking is probably not needed.
(cherry picked from commit d82bc0a29f)
The documentation links for `parentDir()` and `getCurrentDir()` are
broken as they are no longer part of `std/os`. Link changed to
`std/private/ospaths2`.
(cherry picked from commit 9c155eaccc)
