static inline and jextract

[Sundararajan Athijegannathan]

Yes, "static inline" is part of C99

https://en.wikipedia.org/wiki/Inline_function
Inline function - Wikipedia<https://en.wikipedia.org/wiki/Inline_function>
In the C and C++ programming languages, an inline function is one qualified with the keyword inline; this serves two purposes: . It serves as a compiler directive that suggests (but does not require) that the compiler substitute the body of the function inline by performing inline expansion, i.e. by inserting the function code at the address of each function call, thereby saving the overhead ...
en.wikipedia.org


PS. perhaps static inline stuff should be auto-filtered by jextract - given that these symbols cannot be exported from shared objects anyway?

-Sundar

________________________________
From: jextract-dev <jextract-dev-retn at openjdk.org> on behalf of Manuel Bleichenbacher <manuel.bleichenbacher at gmail.com>
Sent: 05 September 2022 21:02
To: Maurizio Cimadamore <maurizio.cimadamore at oracle.com>
Cc: jextract-dev at openjdk.org <jextract-dev at openjdk.org>
Subject: Re: static inline and jextract

Talking of things to skip:

Windows constants like "GUID_DEVINTERFACE_USB_DEVICE" should also be skipped. Through two layers of macros, it resolves to:

extern "C" const GUID __declspec(selectany) GUID_DEVINTERFACE_USB_DEVICE
    = { 0xA5DCBF10L, 0x6530, 0x11D2, { 0x90, 0x1F,  0x00,  0xC0,  0x4F,  0xB9,  0x51,  0xED } };

Can you spot the problem? It's a definition, and not a declaration. So there can't possibly be a symbol for it in an external library.

At the moment, jextract will generate code, which then fails with "unresolved symbol: GUID_DEVINTERFACE_USB_DEVICE". It clearly should be skipped.

To reproduce it:

windows_headers.h:
#include <windows.h>
#include <initguid.h>
#include <usbiodef.h>


set SDK_DIR=C:\Program Files (x86)\Windows Kits\10\Include\10.0.22000.0
jextract --source ^
  -D _AMD64_ -D _M_AMD64=100 -D UNICODE -D _UNICODE ^
  -I "%SDK_DIR%\um" ^
  -I "%SDK_DIR%\shared" ^
  --include-var GUID_DEVINTERFACE_USB_DEVICE ^
  windows_headers.h

BTW: "static inline" is a somewhat newer addition to C but it's plain C, isn't?


On Mon, Sep 5, 2022 at 5:10 PM Maurizio Cimadamore <maurizio.cimadamore at oracle.com<mailto:maurizio.cimadamore at oracle.com>> wrote:

On 05/09/2022 12:30, Manuel Bleichenbacher wrote:
> Is there a reason to treat inline static functions different from
> function-like macros?

IMHO they should be treated similarly - e.g. they should be skipped.

Also, I thought jextract skipped stuff that was not plain C, so I'm
surprised to see symbols being generated for "inline" functions. Maybe
we're missing some checks?

Maurizio

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