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digitalmars.D - ImportC and druntime's importc.h and __builtins.di

reply Walter Bright <newshound2 digitalmars.com> writes:
Lots of people are trying out ImportC, which is good news! Lots of people 
encounter a problem here and there with a strange error message emanating from 
the compiler when compiling a .h file.

A good way to find out what is causing this error message is to run the C 
preprocessor (such as cpp) over the .c file that #include's it, and direct the 
result into a .i file.

A bit more work, and usually the offending line in the .i file is isolated.

A large number of these errors result from the .h file making use of some 
bizzaro C language extension, that nobody who makes these .h files seems to be 
able to resist.

It is not practical for ImportC to implement every C compiler's nutburger 
extension. But usually there is a way to write a C macro to provide a
workaround.

This is the job of druntime/src/importc.h, which is automatically #include'd by 
ImportC:

https://github.com/dlang/dmd/blob/master/druntime/src/importc.h

To fix the problem you've encountered, adding a macro to importc.h can get your 
code moving again (and please file a bugzilla or a PR so everyone can take 
advantage of your findings!).

Another file used to compensate for nutburger C compiler extensions is 
__builtins.di:

https://github.com/dlang/dmd/blob/master/druntime/src/__builtins.di

which, having access to D's constructions, can often fake a C compiler 
extension. __builtins.di is also automatically imported by every compilation of 
an ImportC C file.
Sep 03 2023
parent reply Adam Wilson <flyboynw gmail.com> writes:
On Sunday, 3 September 2023 at 08:55:13 UTC, Walter Bright wrote:

 https://github.com/dlang/dmd/blob/master/druntime/src/importc.h

 To fix the problem you've encountered, adding a macro to 
 importc.h can get your code moving again (and please file a 
 bugzilla or a PR so everyone can take advantage of your 
 findings!).

 Another file used to compensate for nutburger C compiler 
 extensions is __builtins.di:

 https://github.com/dlang/dmd/blob/master/druntime/src/__builtins.di

 which, having access to D's constructions, can often fake a C 
 compiler extension. __builtins.di is also automatically 
 imported by every compilation of an ImportC C file.


importc.h is how I nullified MSFT's idiotic #define based 
metadata annotations that liter all of their header files while 
at DConf. One small step closer to jettisoning the hopelessly 
outdated MinGW header translations from the Windows XP era...

It Works.
Sep 09 2023
parent reply Walter Bright <newshound2 digitalmars.com> writes:
On 9/9/2023 7:19 PM, Adam Wilson wrote:

 importc.h is how I nullified MSFT's idiotic #define based metadata annotations 
 that liter all of their header files while at DConf. One small step closer to 
 jettisoning the hopelessly outdated MinGW header translations from the Windows 
 XP era...
 
 It Works.


I hope you did a PR for it!

Microsoft headers also include inline assembly with no way to turn it off.
Sigh. 
I was forced to try supporting their inline assembler.
Sep 10 2023
parent reply Adam Wilson <flyboynw gmail.com> writes:
On Monday, 11 September 2023 at 01:30:16 UTC, Walter Bright wrote:

 On 9/9/2023 7:19 PM, Adam Wilson wrote:

 importc.h is how I nullified MSFT's idiotic #define based 
 metadata annotations that liter all of their header files 
 while at DConf. One small step closer to jettisoning the 
 hopelessly outdated MinGW header translations from the Windows 
 XP era...
 
 It Works.


 I hope you did a PR for it!

 Microsoft headers also include inline assembly with no way to 
 turn it off. Sigh. I was forced to try supporting their inline 
 assembler.


Merged it at DConf. No more SAL nonsense from MSFT headers. Ever.

Microsoft headers are full of aggravation. Speaking of, have you 
had a chance to look at this aggravation yet? 
https://issues.dlang.org/show_bug.cgi?id=24132

I also have this one open: 
https://issues.dlang.org/show_bug.cgi?id=24121
Making ImportC work with DI files can offer us a potential 
fast-path to automated binding generation directly from the 
compiler. It'll take more work to make this work with the MSFT 
headers, but once we do, we could theoretically replace that 
giant pile of nastiness that are the MinGW translations with a 
nice, clean ImportC auto-generated files that are much easier to 
keep synchronized with the canonical Windows SDK headers.
Sep 10 2023
parent reply Adam D Ruppe <destructionator gmail.com> writes:
On Monday, 11 September 2023 at 03:44:20 UTC, Adam Wilson wrote:

 Making ImportC work with DI files can offer us a potential 
 fast-path to automated binding generation directly from the 
 compiler


We also already have automated bindings from the projections 
thing microsoft put out

https://github.com/microsoft/win32metadata/tree/main

D - https://github.com/rumbu13/windows-d (Community)
Sep 11 2023
parent reply Walter Bright <newshound2 digitalmars.com> writes:
On 9/11/2023 5:30 AM, Adam D Ruppe wrote:

 On Monday, 11 September 2023 at 03:44:20 UTC, Adam Wilson wrote:

 Making ImportC work with DI files can offer us a potential fast-path to 
 automated binding generation directly from the compiler


 
 We also already have automated bindings from the projections thing microsoft
put 
 out
 
 https://github.com/microsoft/win32metadata/tree/main
 
 D - https://github.com/rumbu13/windows-d (Community)


I didn't know that existed. Nice! Are you using it?
Sep 11 2023
next sibling parent Walter Bright <newshound2 digitalmars.com> writes:
On 9/11/2023 11:32 AM, Walter Bright wrote:

 We also already have automated bindings from the projections thing microsoft 
 put out





This should work for ImportC C files that use it. However, if ImportC is used
on 
an existing project, it'll expect the Windows .h files to work. I doubt we'll 
ever get them to work perfectly with all the wacky idiosyncrasies in them, but 
we'll do what we can.
Sep 11 2023
prev sibling parent Adam D Ruppe <destructionator gmail.com> writes:
On Monday, 11 September 2023 at 18:32:15 UTC, Walter Bright wrote:

 I didn't know that existed. Nice! Are you using it?


No, I find the existing druntime ones to work well and supplement 
with with private extern(C) decls when I have to.

I just don't want people to forget that thing exists.
Sep 11 2023