Re: [dpdk-dev] [PATCH] eal/windows: fix build warnings in MinGW

[Tal Shnaiderman <talshn@nvidia.com>]

> Subject: Re: [dpdk-dev] [PATCH] eal/windows: fix build warnings in MinGW
> 
> External email: Use caution opening links or attachments
> 
> 
> > Subject: Re: [PATCH] eal/windows: fix build warnings in MinGW
> >
> > External email: Use caution opening links or attachments
> >
> >
> > Hi Tal,
> >
> > 2021-04-18 19:04 (UTC+0000), Tal Shnaiderman:
> > > > Subject: Re: [PATCH] eal/windows: fix build warnings in MinGW
> > > >
> > > > External email: Use caution opening links or attachments
> > > >
> > > >
> > > > 18/04/2021 19:08, Tal Shnaiderman:
> > > > > the strncasecmp marco defined in rte_os_shim.h is already
> > > > > defined in MinGW-w64, as a result the compiler prints out the
> > > > > warning below on function redefinition whenever compiling a file
> > > > > including the
> > header.
> > > > >
> > > > > ..\lib/librte_eal/windows/include/rte_os_shim.h:21:
> > > > > warning: "strncasecmp" redefined #define strncasecmp(s1, s2,
> > > > > count) _strnicmp(s1, s2, count)
> > > >
> > > > Why the tests are passing? Are we allowing warnings in build test?
> > >
> > > It's a good question, I see CI is passing without warnings, Dmitry
> > > can you
> > reproduce it?
> > >
> > > On my side the collision is with the following file:
> > >
> > > C:/mingw-w64/x86_64/mingw64/x86_64-w64-
> > mingw32/include/string.h:119:
> > > note: this is the location of the previous definition  #define
> > > strncasecmp _strnicmp
> > >
> > > I'm using:
> > > -gcc (x86_64-win32-seh-rev0, Built by MinGW-W64 project) 8.1.0
> > > -meson
> > > 0.53.2
> >
> > I can't reproduce it using the same versions.
> > Do you invoke meson with other options than "-Dexamples=..."?
> 
> This is the meson line I'm using:
> 
> meson "-Dexamples=helloworld" build --wipe --default-library=static --
> buildtype debug
> 
> The problem however is that MinGW's string.h defines the macro in line 119,
> for some reason my build includes it and the rest doesn't.

Hi Dmitry,

I also noticed warnings in clang on my setup that are related to rte_os_shim.h:

[185/314] Compiling C object drivers/a715181@@tmp_rte_common_mlx5@sta/common_mlx5_mlx5_common_mp.c.obj.
In file included from ../drivers/common/mlx5/mlx5_common_mp.c:13:
In file included from ..\drivers\common/mlx5/mlx5_common_utils.h:8:
In file included from ..\drivers\common/mlx5/mlx5_common.h:17:
..\lib/librte_eal/windows/include\rte_os_shim.h:22:51: warning: token pasting of ',' and __VA_ARGS__ is a GNU extension [-Wgnu-zero-variadic-macro-arguments]
#define open(path, flags, ...) _open(path, flags, ##__VA_ARGS__)
                                                  ^
However don't see it in CI, I'm using clang version 9.0.1