<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/127327>127327</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-cl] The `[[noreturn]]` attribute causes parsing to crash by declaring a concurrent function that returns.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          YuHuanTin
      </td>
    </tr>
</table>

<pre>
    ```
D:\LLVM\bin\clang-cl.exe   -TP -DCRCPP_IMPORT_API -imsvcD:\Clion\vcpkg\installed\x64-windows\include /DWIN32 /D_WINDOWS /EHsc /Ob0 /Od /RTC1 -std:c++latest -MDd -Zi /clang:-Wall -Wextra -Wpedantic -Wconversion /permissive- /showIncludes /FoCMakeFiles\New.dir\main.cpp.obj /FdCMakeFiles\New.dir\ -c -- D:\Clion\Project\New\main.cpp
D:\Clion\Project\New\main.cpp(7,41): warning: function 'foo' declared 'noreturn' should not return [-Winvalid-noreturn]
    7 | [[noreturn]] concurrencpp::result<void> foo() {
      |                                         ^
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: D:\\LLVM\\bin\\clang-cl.exe -TP -DCRCPP_IMPORT_API -imsvcD:\\Clion\\vcpkg\\installed\\x64-windows\\include /DWIN32 /D_WINDOWS /EHsc /Ob0 /Od /RTC1 -std:c++latest -MDd -Zi /clang:-Wall -Wextra -Wpedantic -Wconversion /permissive- /showIncludes /FoCMakeFiles\\New.dir\\main.cpp.obj /FdCMakeFiles\\New.dir\\ -c -- D:\\Clion\\Project\\New\\main.cpp
1.      <eof> parser at end of file
2.      D:\Clion\Project\New\main.cpp:7:47: parsing function body 'foo'
Exception Code: 0xC0000005
 #0 0x00007ff7e22fcd44 (D:\LLVM\bin\clang-cl.exe+0x77cd44)
 #1 0x00007ff7e22fcb30 (D:\LLVM\bin\clang-cl.exe+0x77cb30)
 #2 0x00007ff7e3a2cf6f (D:\LLVM\bin\clang-cl.exe+0x1eacf6f)
 #3 0x00007ff7e2c95037 (D:\LLVM\bin\clang-cl.exe+0x1115037)
 #4 0x00007ff7e2c9433a (D:\LLVM\bin\clang-cl.exe+0x111433a)
 #5 0x00007ff7e2c93e83 (D:\LLVM\bin\clang-cl.exe+0x1113e83)
 #6 0x00007ff7e2c90eb5 (D:\LLVM\bin\clang-cl.exe+0x1110eb5)
 #7 0x00007ff7e2c90e2a (D:\LLVM\bin\clang-cl.exe+0x1110e2a)
 #8 0x00007ff7e2d41fa8 (D:\LLVM\bin\clang-cl.exe+0x11c1fa8)
 #9 0x00007ff7e2c82167 (D:\LLVM\bin\clang-cl.exe+0x1102167)
#10 0x00007ff7e2c7f6b4 (D:\LLVM\bin\clang-cl.exe+0x10ff6b4)
#11 0x00007ff7e2c76d59 (D:\LLVM\bin\clang-cl.exe+0x10f6d59)
#12 0x00007ff7e2ae8ea5 (D:\LLVM\bin\clang-cl.exe+0xf68ea5)
#13 0x00007ff7e2ae0c12 (D:\LLVM\bin\clang-cl.exe+0xf60c12)
#14 0x00007ff7e2add88a (D:\LLVM\bin\clang-cl.exe+0xf5d88a)
#15 0x00007ff7e36e09e6 (D:\LLVM\bin\clang-cl.exe+0x1b609e6)
#16 0x00007ff7e36e064e (D:\LLVM\bin\clang-cl.exe+0x1b6064e)
#17 0x00007ff7e2143a61 (D:\LLVM\bin\clang-cl.exe+0x5c3a61)
#18 0x00007ff7e21435f2 (D:\LLVM\bin\clang-cl.exe+0x5c35f2)
#19 0x00007ff7e2140366 (D:\LLVM\bin\clang-cl.exe+0x5c0366)
#20 0x00007ff7e213d325 (D:\LLVM\bin\clang-cl.exe+0x5bd325)
#21 0x00007ff7e213bcbe (D:\LLVM\bin\clang-cl.exe+0x5bbcbe)
#22 0x00007ff7e28555cd (D:\LLVM\bin\clang-cl.exe+0xcd55cd)
#23 0x00007ff7e22c4175 (D:\LLVM\bin\clang-cl.exe+0x744175)
#24 0x00007ff7e22c3f68 (D:\LLVM\bin\clang-cl.exe+0x743f68)
#25 0x00007ff7e1fcc0c8 (D:\LLVM\bin\clang-cl.exe+0x44c0c8)
#26 0x00007ff7e1fcb44e (D:\LLVM\bin\clang-cl.exe+0x44b44e)
#27 0x00007ff7e1fcafc7 (D:\LLVM\bin\clang-cl.exe+0x44afc7)
#28 0x00007ff7e1fc2756 (D:\LLVM\bin\clang-cl.exe+0x442756)
#29 0x00007ff7e1fbfed3 (D:\LLVM\bin\clang-cl.exe+0x43fed3)
#30 0x00007ff7e3782bc8 (D:\LLVM\bin\clang-cl.exe+0x1c02bc8)
#31 0x00007ffbdf6b7374 (C:\Windows\System32\KERNEL32.DLL+0x17374)
#32 0x00007ffbe135cc91 (C:\Windows\SYSTEM32\ntdll.dll+0x4cc91)
clang-cl: error: clang frontend command failed due to signal (use -v to see invocation)
clang version 19.1.7
Target: x86_64-pc-windows-msvc
Thread model: posix
InstalledDir: D:\LLVM\bin
clang-cl: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang-cl: note: diagnostic msg: F:\Temp\WinTemp\main-efd334.cpp
clang-cl: note: diagnostic msg: F:\Temp\WinTemp\main-efd334.sh
clang-cl: note: diagnostic msg: 

********************
ninja: build stopped: subcommand failed.
```

The full code
```c++
#include <concurrencpp/concurrencpp.h>

concurrencpp::result<void> bar() {
 co_return;
}

[[noreturn]] concurrencpp::result<void> foo() {
 co_await bar();
}


```

Yes, I know it's a bad practice to flag `[[noreturn]]` on a function that might return, but it should get a warn or error, but the compiler crashes

the crash file

[crash.zip](https://github.com/user-attachments/files/18811028/crash.zip)
</pre>
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