Inside a signal handler, you cannot allocate memory because the signal
handler, being implemented with a C
[`signal`](https://en.cppreference.com/w/c/program/signal) call, can be
called _during_ a memory allocation - when that happens, the CTRL-C
handler causes a segfault and/or other inconsistent state.
Similarly, the call can happen from a non-nim thread or inside a C
library function call etc, most of which do not support reentrancy and
therefore cannot be called _from_ a signal handler.
The stack trace facility used in the default handler is unfortunately
beyond fixing without more significant refactoring since it uses
garbage-collected types in its API and implementation.
As an alternative to https://github.com/nim-lang/Nim/pull/25110, this PR
removes the most problematic signal handler, namely the one for SIGINT
(ctrl-c) - SIGINT is special because it's meant to cause a regular
shutdown of the application and crashes during SIGINT handling are both
confusing and, if turned into SIGSEGV, have downstream effects like core
dumps and OS crash reports.
The signal handlers for the various crash scenarios remain as-is - they
may too cause their own crashes but we're already going down in a bad
way, so the harm is more limited - in particular, crashing during a
crash handler corrupts `core`/crash dumps. Users wanting to keep their
core files pristine should continue to use `-d:noSignalHandler` - this
is usually the better option for production applications since they
carry more detail than the Nim stack trace that gets printed.
Finally, the example of a ctrl-c handler performs the same mistake of
calling `echo` which is not well-defined - replace it with an example
that is mostly correct (except maybe for the lack of `volatile` for the
`stop` variable).
Theoretical Benefits / Plans:
- Typed assembler-like language.
- Allows for a CPS transformation.
- Can replace the existing C backend by a new C backend.
- Can replace the VM.
- Can do more effective "not nil" checking and static array bounds
checking.
- Can be used instead of the DFA.
- Easily translatable to LLVM.
- Reasonably easy to produce native code from.
- Tiny memory consumption. No pointers, no cry.
**In very early stages of development.**
Todo:
- [x] Map Nim types to IR types.
- [ ] Map Nim AST to IR instructions:
- [x] Map bitsets to bitops.
- [ ] Implement string cases.
- [ ] Implement range and index checks.
- [x] Implement `default(T)` builtin.
- [x] Implement multi string concat.
- [ ] Write some analysis passes.
- [ ] Write a backend.
- [x] Integrate into the compilation pipeline.
* system refactor, move out 600 lines
* compilation, slice, backwardsindex, misc_num moved out of system
* some procs/types moved into arithmetics, basic_types
* system no longer depends on syncio
* some procs moved around to fit with their surroundings
* make exceptions an import, old ops to misc_num
* move instantiationInfo back
* move back nim version, fix windows echo
* include compilation
* better docs for imported modules, fix unsigned ops
also remove ze, ze64, toU8, toU16, toU32 with nimPreviewSlimSystem
* fix terminal
* workaround IC test & weird csize bug, changelog
* move NimMajor etc back to compilation, rebase for CI
* try ic fix
* form single `indices`, slim out TaintedString, try fix IC
* fix CI, update changelog, addQuitProc
* fix CI
* try fix CI
* actually fix CI finally hopefully
* Update lib/system/compilation.nim
Co-authored-by: ringabout <43030857+ringabout@users.noreply.github.com>
* update kochdocs
* hopefully fix csize uses for slimsystem
* fix tquit
Co-authored-by: ringabout <43030857+ringabout@users.noreply.github.com>
* fix vcc rawsetjmp
* changing `_longjmp()` to `longjmp()` and
`_setjmp()` to `setjmp()`
* fix
* fix setjmp to clangcl on Windows
* fix genTrySetjmp() to clangcl on Windows
* Windows: enable nimRawSetjmp by default
See #19197. The default setjmp can randomly segfault on windows
* Attempt to disable the flag for bootstraping
* Disable styleCheck for c_setjmp
* nimRawSetjmp: support Windows
Using `_setjmp()` directly is required to avoid some rare (but very
annoying) exception-related stack corruption leading to segfaults on
Windows, with Mingw-w64 and SEH.
More details: https://github.com/status-im/nimbus-eth2/issues/3121
Also add "nimBuiltinSetjmp" - mostly for benchmarking.
* fix for Apple's Clang++
* Porting Nim to run on Zephyr.
Includes changes to `std/net`.
Squashed commit of the following:
tweaking more memory / malloc things
revert back bitmasks
tweaking nim to use kernel heap as C malloc doesn't work
fixing socket polling on zephyr
cleanup getting maximum sockets for process or for rtos'es
reorganizing and fixing net for async / system
merge netlite changes back into nativesockets
merge netlite changes back into nativesockets
reverting native sockets back
tweaking nim / zephyr network
adding option to run 'net-lite' from linux
bridging zephyr's max connections
fixing net errors
fixing compilation with getAddrString
fixing compilation with getAddrString
experimenting with a nativesockets_lite ... getAddrString
experimenting with a nativesockets_lite ... getAddrString
experimenting with a nativesockets_lite ... getLocalAddr
experimenting with a nativesockets_lite ... getLocalAddr
experimenting with a nativesockets_lite ...
add note regarding incorrect FreeRTOS Sockadd_in fields
changing to NIM_STATIC_ASSERT
cleaning up the static_assert error messages
cleaning up the static_assert error messages
setting up static assert ftw!
testing compile time asserts
reworking Sockaddr objects to more closely match various platforms
reworking Sockaddr objects to more closely match various platforms
reworking Sockaddr objects to more closely match various platforms
finding missing items (issue #18684)
fixup posix constants (issue #18684)
adding plumbing for zephyr os (issue #18684)
adding plumbing for zephyr os (issue #18684)
* fixing constant capitalizations
* remove extra debug prints and fix TSa_Family/cint issue
* remove extra debug prints and fix TSa_Family/cint issue
* Porting Nim to run on Zephyr.
Includes changes to `std/net`.
Squashed commit of the following:
tweaking more memory / malloc things
revert back bitmasks
tweaking nim to use kernel heap as C malloc doesn't work
fixing socket polling on zephyr
cleanup getting maximum sockets for process or for rtos'es
reorganizing and fixing net for async / system
merge netlite changes back into nativesockets
merge netlite changes back into nativesockets
reverting native sockets back
tweaking nim / zephyr network
adding option to run 'net-lite' from linux
bridging zephyr's max connections
fixing net errors
fixing compilation with getAddrString
fixing compilation with getAddrString
experimenting with a nativesockets_lite ... getAddrString
experimenting with a nativesockets_lite ... getAddrString
experimenting with a nativesockets_lite ... getLocalAddr
experimenting with a nativesockets_lite ... getLocalAddr
experimenting with a nativesockets_lite ...
add note regarding incorrect FreeRTOS Sockadd_in fields
changing to NIM_STATIC_ASSERT
cleaning up the static_assert error messages
cleaning up the static_assert error messages
setting up static assert ftw!
testing compile time asserts
reworking Sockaddr objects to more closely match various platforms
reworking Sockaddr objects to more closely match various platforms
reworking Sockaddr objects to more closely match various platforms
finding missing items (issue #18684)
fixup posix constants (issue #18684)
adding plumbing for zephyr os (issue #18684)
adding plumbing for zephyr os (issue #18684)
* fixing constant capitalizations
* remove extra debug prints and fix TSa_Family/cint issue
* remove extra debug prints and fix TSa_Family/cint issue
* fixing PR issues
* Porting Nim to run on Zephyr.
Includes changes to `std/net`.
Squashed commit of the following:
tweaking more memory / malloc things
revert back bitmasks
tweaking nim to use kernel heap as C malloc doesn't work
fixing socket polling on zephyr
cleanup getting maximum sockets for process or for rtos'es
reorganizing and fixing net for async / system
merge netlite changes back into nativesockets
merge netlite changes back into nativesockets
reverting native sockets back
tweaking nim / zephyr network
adding option to run 'net-lite' from linux
bridging zephyr's max connections
fixing net errors
fixing compilation with getAddrString
fixing compilation with getAddrString
experimenting with a nativesockets_lite ... getAddrString
experimenting with a nativesockets_lite ... getAddrString
experimenting with a nativesockets_lite ... getLocalAddr
experimenting with a nativesockets_lite ... getLocalAddr
experimenting with a nativesockets_lite ...
add note regarding incorrect FreeRTOS Sockadd_in fields
changing to NIM_STATIC_ASSERT
cleaning up the static_assert error messages
cleaning up the static_assert error messages
setting up static assert ftw!
testing compile time asserts
reworking Sockaddr objects to more closely match various platforms
reworking Sockaddr objects to more closely match various platforms
reworking Sockaddr objects to more closely match various platforms
finding missing items (issue #18684)
fixup posix constants (issue #18684)
adding plumbing for zephyr os (issue #18684)
adding plumbing for zephyr os (issue #18684)
* fixing constant capitalizations
* remove extra debug prints and fix TSa_Family/cint issue
* remove extra debug prints and fix TSa_Family/cint issue
* Remerge
* fixing constant capitalizations
* remove extra debug prints and fix TSa_Family/cint issue
* remove extra debug prints and fix TSa_Family/cint issue
* fixing PR issues
* fix maxDescriptors on zephyr/freertos
* move maxDescriptors to selector.nim -- fixes compile issue
* change realloc impl on zephyr to match ansi c behavior
* change realloc impl on zephyr to match ansi c behavior
* force compileOnly mode for tlwip
Co-authored-by: Jaremy J. Creechley <jaremy.creechley@wavebaselabs.com>
Co-authored-by: Jaremy Creechley <jaremy.creechley@panthalassa.com>
* Cleanup, remove lib/system/allocators.nim. seqs_v2 and strs_v2 now use
allocShared0 by default.
* Fixed -d:useMalloc allocShared / reallocShared / deallocShared. These now use the alloc/dealloc/realloc implementation that also takes care of zeroing memory at realloc.
* Removed debug printfs
* Removed unpairedEnvAllocs() from tests/destructor/tnewruntime_misc
* More mmdisp cleanups. The shared allocators do not need to zero memory or throw since the regular ones already do that
* Introduced realloc0 and reallocShared0, these procs are now used by
strs_v2 and seqs_v2. This also allowed the -d:useMalloc allocator to
drop the extra header with allocation length.
* Moved strs_v2/seqs_v2 'allocated' flag into 'cap' field
* Added 'getAllocStats()' to get low level alloc/dealloc counters. Enable with -d:allocStats
* *allocShared implementations for boehm and go allocators now depend on the proper *allocImpl procs
Stack traces on an unbuffered stderr get out of sync with line-buffered
stdout - usually on Windows terminals or CI logs. This fixes it by
calling C's fflush() on the output buffer in the procedure used for
printing stack traces.
* move IO subsystem into its own module; refs #10385
* make standalone test compile again
* make C++ examples compile again
* make more tests green
* make sysAssert and gcAssert work again
* posix_other: Haiku now has spawn.h
This is added per https://dev.haiku-os.org/ticket/13446
* posix_other: Add Haiku specific Dirent members
* cpuinfo: Add an implementation for Haiku
* distros: Add basic Haiku support
* encodings: update Haiku support
* fenv, math: Haiku now provides libm
* times: Add Haiku struct members
* ansi_c, osalloc: Add Haiku constants
* threads: Add Haiku support
* testament: Haiku uses LIBRARY_PATH
* nim.cfg: Update Haiku support
libnetwork should only be linked if network functions are used
* threads: Haiku does not support -pthread switch
* tworkingdir: Haiku's env is in /bin
* posix_other: add SIGKILLTHR for Haiku
* sockets: link with libnetwork on Haiku
* coro: correct ucontext.h location
http://pubs.opengroup.org/onlinepubs/009696699/basedefs/ucontext.h.html
* coro: ucontext backend is not available on Haiku
Haiku doesn't provide the <ucontext.h> header, as it was removed from POSIX
* coro: fix setjmp backend
The compiler does not allow statements after a noreturn function
* nativesockets: Haiku doesn't support AI_V4MAPPED
* system: hostOS can contains "haiku"
* os: add support for Haiku's packagefs
packagefs is read-only, but there are writable holes to the underlying
file system as well
* os: update constant for Haiku
* Add config section for Nintendo Switch
* Add compiler configuration for Nintendo Switch and it's CPU
* Add specific lib code for Nintendo Switch
* Add GC support for Nintendo Switch
* Update changelog for Nintendo Switch
* Update changelog with more info about fixed paths
* Cleaned up GC memory management a bit
* Relocate docs for Switch
* Rename aarch64NoneElfGcc to nintendoSwitchGCC
* Remove armv8a57
* Fix installer.ini
* Reuse code in linux and amd64
* Add posix defs for nintendo switch
* Add more defined sections for nintendo switch
* Remove old comment
* Add what's not supported for Nintendo Switch docs
* Make nintendoswitch == posix
* Remove DEVKITPRO references from nim.cfg
* Make PR extccomp changes
* Remove Result type alias
* Add separate switch consts file
* Update docs for nintendo switch
* Fix travis errors with undefined consts and add correct wait.h procs
* Fix kqueue.nim and ansi_c.nim to support dragonfly.
* Fix ioselectors.nim, threads.nim to support dragonfly.
* Fix deprecated dealloc call in tioselectors.nim.
* Fix tfsmonitor.nim test to run only on Linux.
* Fix osproc.nim return wrong exit codes.
* Fix getAppFilename() for dragonfly.
* Fix proper exit code handling.
