False positive error on C nested structs

Nobody has claimed this yet.

Type: Bug

VSCode claims that the assignment to foo.bar below is an error "a value of type "struct Bar" cannot be assigned to an entity of type "struct Bar" C/C++(513)"

The code compiles cleanly both with gcc and clang (with -Wall -Wextra in both cases). I believe it is ISO C compliant, although a fairly uncommon usage. (In C nested, named, structs become part of the global namespace, which is different from C++.)

// C not C++.
struct Foo {
    struct Bar {
        int x;
    } bar;
};

int main(void)
{
    struct Foo foo;
    foo.bar = (struct Bar) {0}; // Incorrectly marked as an error by VSCode.
    return foo.bar.x;
}

Extension version: 1.22.11
VS Code version: Code 1.95.3 (f1a4fb101478ce6ec82fe9627c43efbf9e98c813, 2024-11-13T14:50:04.152Z)
OS version: Linux x64 6.11.7-300.fc41.x86_64
Modes:

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz (8 x 3700)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: disabled_software vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: disabled_off webnn: disabled_off
Load (avg)	1, 1, 1
Memory (System)	62.48GB (36.96GB free)
Process Argv	--crash-reporter-id 73c5a75d-b680-4906-94d8-412f0182e453
Screen Reader	no
VM	0%
DESKTOP_SESSION	mate
XDG_CURRENT_DESKTOP	MATE
XDG_SESSION_DESKTOP	mate
XDG_SESSION_TYPE	x11

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Start with the minimal nested-struct C reproduction in the issue and inspect how the C/C++ extension analyzes the assignment to foo.bar. Compare the extension's diagnostic with GCC and Clang results. Done means valid ISO C produces no false type-mismatch error in VS Code, with regression coverage added if the project provides a suitable test location.

Written by the indexing model from the issue text.

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