From: "Rémi Bernon" <rbernon@codeweavers.com>
Subject: Re: [PATCH 1/4] widl: Fix C++ RuntimeClass string constants declaration.
Message-Id: <7073eb89-e39c-2362-f9eb-f83527ffedbb@codeweavers.com>
Date: Fri, 26 Feb 2021 15:24:33 +0100
In-Reply-To: <b6ece317-488d-eaf3-6cbe-6faa4e7c6ba1@codeweavers.com>
References: <20210226084306.2784145-1-rbernon@codeweavers.com> <b6ece317-488d-eaf3-6cbe-6faa4e7c6ba1@codeweavers.com>

On 2/26/21 1:46 PM, Jacek Caban wrote:
> Hi Rémi,
> 
> On 26.02.2021 09:43, Rémi Bernon wrote:
>> MinGW g++ requires initialized selectany to have extern linkage.
>>
>> When supported, we define WCHAR as char16_t, which requires u"" string
>> literal. When not supported, and when WCHAR is unsigned short, it then
>> requires to use an array initializer instead of a L"" string literal.
>>
>> Signed-off-by: Rémi Bernon <rbernon@codeweavers.com>
>> ---
>>   tools/widl/header.c | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>>
>> diff --git a/tools/widl/header.c b/tools/widl/header.c
>> index a472af49066..23de3e12aca 100644
>> --- a/tools/widl/header.c
>> +++ b/tools/widl/header.c
>> @@ -1836,8 +1836,18 @@ static void write_runtimeclass(FILE *header, 
>> type_t *runtimeclass)
>>       fprintf(header, "#ifndef RUNTIMECLASS_%s_DEFINED\n", c_name);
>>       fprintf(header, "#define RUNTIMECLASS_%s_DEFINED\n", c_name);
>>       fprintf(header, "#if defined(_MSC_VER) || defined(__MINGW32__)\n");
>> +    fprintf(header, "#ifdef __cplusplus\n");
>> +    fprintf(header, "#if defined(WINE_UNICODE_NATIVE)\n");
>> +    fprintf(header, "extern const DECLSPEC_SELECTANY WCHAR 
>> RuntimeClass_%s[] = L\"%s\";\n", c_name, name);
>> +    fprintf(header, "#else\n");
>> +    fprintf(header, "extern const DECLSPEC_SELECTANY WCHAR 
>> RuntimeClass_%s[] = {", c_name);
>> +    for (i = 0, len = strlen(name); i < len; ++i) fprintf(header, 
>> "'%c',", name[i]);
>> +    fprintf(header, "0};\n");
> 
> 
> If we need the second case anyway, then I'm not sure if there is a point 
> in the first one. I would expect the {...} initializer to produce the 
> same result without having to worry about actual WCHAR type. With that, 
> maybe we could reorder things a bit to simplify it. Would something like 
> that work?
> 
> 
> #if !defined(__MINGW32__) && !defined(_MSC_VER)
> 
> static const WCHAR RuntimeClass_...[] = {...};
> 
> #elif defined(__GNUC__) && !defined(__cplusplus)
> 
> const DECLSPEC_SELECTANY WCHAR RuntimeClas_...[] = L"...";
> 
> #else
> 
> extern const DECLSPEC_SELECTANY WCHAR RuntimeClas_...[] = {...};
> 
> #endif
> 
> 
> Thanks,
> 
> Jacek
> 
> 

Yeah, I guess it's more or less equivalent to folding my two __cplusplus 
cases above to use extern qualifier and an array initializer.
-- 
Rémi Bernon <rbernon@codeweavers.com>