Linux: Incorrect Intelli-Sense Error: global wchar_t array initialized with wide character string literal

[samival]

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Environment

• OS and Version: Linux (Ubuntu based 22.04 & 20.04 on WSL)
• VS Code Version: 1.91.1
• C/C++ Extension Version: 2.0.0

Bug Summary and Steps to Reproduce

Steps to reproduce: Create a .c file with a global wchar_t array and initialize it with a wide char string literal (L"..." ) i.e. wchar_t s[] = L"ABC";

Bug Summary: On Linux the Intelli-Sense Engine seems to identify wide-character string literals as unsigned int arrays while wchar_t is typedef'd by GCC to be signed int, causing a type mismatch which triggers an incorrect error.

The error shown is: a value of type "unsigned int [4]" cannot be used to initialize an entity of type "wchar_t []" (aka "int []")C/C++(144)

Initializing a const wchar_t * doesn't produce an error. Initializing in a local scope doesn't produce an error.

Some potentially relevant VSCode settings:

C_Cpp.intelliSenseEngine = deafult
C_Cpp.intelliSenseEngineFallback = disabled

C_Cpp.default.cStandard = C17
(same result for all other available values)

C_Cpp.default.intelliSenseMode = linux-gcc-x64
(or:)
C_Cpp.default.intelliSenseMode = windows-gcc-x64

Configuration and Logs

(some information omitted)


Version: 1.21.3
Current Configuration:
{
    "name": "Linux",
    "cStandard": "c17",
    "cppStandard": "c++17",
    "intelliSenseMode": "linux-gcc-x64",
    "intelliSenseModeIsExplicit": true,
    "cStandardIsExplicit": true,
    "cppStandardIsExplicit": true,
    "mergeConfigurations": false,
}
cpptools version (native): 1.21.3.0

Translation Unit Configurations:

    Process ID: 5302
    Memory Usage: 18 MB
    Compiler Path: /usr/bin/gcc
    Includes:
    System Includes:
        /usr/lib/gcc/x86_64-linux-gnu/9/include
        /usr/local/include
        /usr/include/x86_64-linux-gnu
        /usr/include
    Standard Version: c17
    IntelliSense Mode: linux-gcc-x64
    Other Flags:
        --gcc
        --gnu_version=90400
Total Memory Usage: 18 MB

Other Extensions

No response

Additional context

No response

[Colengms]

Hi @samival . Thanks for reporting this. I can reproduce the issue. We'll investigate.

[Rybasum]

When GCC uses the -fshort-wchar compiler switch (like when compiling U-Boot), Intellisense should be informed about this in the settings of C/C++ Tools extension:

• Find the setting C_Cpp › Default: Compiler Args in @ext:ms-vscode.cpptools
• Add -fshort-wchar

Now, if I write wchar_t* str = L"hehe";, on hovering over wchar_t Intellisense correctly says typedef unsigned short wchar_t. However, hovering over L"hehe" it says (unsigned int [5])L"hehe"

I wonder if this issue is related to the above one.