[PATCH] Add support for IMPORT_NAME_EXPORTAS in ILF (MSVC style) import libraries

[Martin Storsjö]

On Tue, 1 Oct 2024, Jan Beulich wrote:

> On 30.09.2024 23:00, Martin Storsjö wrote:
>> This import name type is formally yet undocumented, but MSVC
>> produces/supports it, primarily for ARM64EC import libraries.
>>
>> LLVM/LLD also supports this import name type. Since recently,
>> llvm-dlltool also uses this type for certain kinds of renamed imports
>> (that are easy to do in the long style import libraries produced by
>> GNU dlltool, but require this name type in short import libraries).
>>
>> This name type contains a third string, in addition to the symbol
>> name and the DLL name, indicating the actual imported name to
>> reference in the import tables - which now can be distinct different
>> from the symbol name on the object file level.
>
> The change looks plausible for what is described above, yet even if the
> form is formally undocumented, some kind of reference must exist
> somewhere. Such a reference is imo quite relevant to have here.

Sure; 
https://github.com/llvm/llvm-project/commit/8f23464a5d957242c89ca6f33d4379c42519cd81 
and 
https://github.com/llvm/llvm-project/commit/7b275aa2438c22604505d618dd37ee60052f2800 
show how the same import name type was added in LLVM; those two are 
probably the first public references to the type.

I can amend the commit message to reference these.

>> --- a/include/coff/pe.h
>> +++ b/include/coff/pe.h
>> @@ -338,6 +338,7 @@ typedef struct
>>  #define IMPORT_NAME		1
>>  #define IMPORT_NAME_NOPREFIX	2
>>  #define IMPORT_NAME_UNDECORATE	3
>> +#define IMPORT_NAME_EXPORTAS    4
>
> Please use tab padding here, just like the neighboring lines do.

Oh, oops, I tried to get that consistent for the code, but I missed this 
one. Will amend the commit with that change.

// Martin