Compiling with --noCppExceptions option generates exception handling C++ code

[demotomohiro]

Description

Compiling Nim code with cpp and --noCppExceptions generates C++ exception handling code.
If compiled with --passC:-fno-exceptions option to disable C++ exception, backend C++ compiler produces compile error.

testcpp.nim:

echo "hello"

Nim Version

Nim Compiler Version 2.1.1 [Linux: amd64]
Compiled at 2023-11-28
Copyright (c) 2006-2023 by Andreas Rumpf

git hash: c31bbb0
active boot switches: -d:release

Current Output

$ nim cpp --exceptions:quirky --passC:-fno-exceptions --noCppExceptions testcpp.nim 
CC: ../nim-2.1.1/lib/system.nim
/tmp/nimcache123/testcpp/debug/@m..@snim-2.1.1@slib@ssystem.nim.cpp: In function 'void sysFatal__system_u4758(NimStringV2)':
/tmp/nimcache123/testcpp/debug/@m..@snim-2.1.1@slib@ssystem.nim.cpp:2641:27: error: exception handling disabled, use '-fexcepti
ons' to enable
 2641 |         catch (Exception* T3_) {
      |                           ^~~

Expected Output

With `--noCppExceptions` option, Nim doesn't produce C++ exception handling code and backend C++ compiler compiles generated Code without error even if C++ exception is disabled.

Possible Solution

No response

Additional Information

Compiling with following command line success without errors:

nim cpp --exceptions:quirky --passC:-fno-exceptions  testcpp.nim 
nim cpp --exceptions:quirky --passC:-fno-exceptions -d:noCppExceptions testcpp.nim 

It seems nocppexceptions command line option defines noCppExceptions in
https://github.com/nim-lang/Nim/blob/devel/compiler/commands.nim#L1060
but Nim generates exception handling C++ code.