Add support for varargs. #344
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| if (cursor is FunctionDecl functionDecl) | ||
| { | ||
| if (functionDecl.IsVariadic) | ||
| { | ||
| return CallingConvention.Cdecl; | ||
| } | ||
| } |
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This needs to support remapping still. The default should definitely be Cdecl, but ClangSharp supports users doing any kind of remapping, even ones that technically may not make sense.
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The document of __stdcall indicates that even the vararg function is marked as __stdcall, the compiler makes it a __cdecl. Therefore I force Cdecl here.
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Yes, but that's not necessarily true for any and all potential platforms. ClangSharp has reasonable defaults and allows devs to override the default to fit their own needs.
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I think we are generating proper dll imports. If a programmer writes a method like
extern "C" int __stdcall foo(...);The compiler won't raise errors. However, if we generate bindings like
[DllImport("foo.dll", CallingConvention = CallingConvention.StdCall)]
static extern int foo(__arglist);The program will raise runtime System.TypeLoadException says that varargs function should use cdecl.
...Sharp.PInvokeGenerator.UnitTests/CSharpCompatibleWindows/FunctionDeclarationDllImportTest.cs
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Sorry for the delay in reviewing this. It generally looks correct to me but has a couple fixups that would be good to include. There should ideally be some handling for a variadic function pointer as well. C# doesn't support them, but ClangSharp still needs to generate something (likely just a diagnostic indicating it couldn't be handled and falling back to |
When the param name is empty. Actually the only possible case is when type is __arglist.
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According to microsoft/win32metadata#917 and microsoft/win32metadata#33 , the win32 metadata doesn't recognize the varargs declarations, which gives much inconvenience. This PR adds simple dll-import support for varargs, and generate C# code with undocumented keyword
__arglist.