<p>I'm having this issue too, on Windows 10, types are not highlighted correctly inside <code>extern "C"</code> blocks (whether guarded or not). For example,</p>

<div class="highlight highlight-source-c"><pre>#<span class="pl-k">ifdef</span> __cplusplus
<span class="pl-k">extern</span> <span class="pl-s"><span class="pl-pds">"</span>C<span class="pl-pds">"</span></span> {
#endif
<span class="pl-k">typedef</span> <span class="pl-k">struct</span> SomeStruct SomeTypedef;
<span class="pl-k">struct</span> SomeStruct
{
    <span class="pl-k">int</span> x;
};
#<span class="pl-k">ifdef</span> __cplusplus
}
#<span class="pl-k">endif</span></pre></div>

<p>Doesn't highlight the type name "SomeTypedef" in C, but it does for the "SomeStruct". If I switch the filetype to C++, neither type is highlighted.</p>

<p>It must be Windows-specific, I know this works fine Linux for sure.</p>

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