Re: [dpdk-dev] [PATCH 4/4] devtools: add Windows cross-build test with MinGW

[Thomas Monjalon <thomas@monjalon.net>]

15/06/2020 00:57, Thomas Monjalon:
> The Meson cross file is renamed from meson_mingw.txt to cross-mingw,
> and is added to test-meson-builds.sh.
> 
> The only example supported on Windows so far is "helloworld",
> that's why the default list of examples is overriden.
> 
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> ---

There is a warning with MinGW on Linux:

In file included from lib/librte_eal/include/rte_eal.h:15,
                 from lib/librte_eal/common/eal_common_options.c:26:
lib/librte_eal/common/eal_common_options.c:
	In function ‘eal_adjust_config’:
lib/librte_eal/windows/include/sched.h:63:55: error:
	‘default_set._bits[1]’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
   63 |   (dst)->_bits[_i] = (src1)->_bits[_i] & (src2)->_bits[_i]; \
      |                                                       ^


% x86_64-w64-mingw32-gcc --version
x86_64-w64-mingw32-gcc (GCC) 10.1.0


It looks to be a false positive, but we need to find a way to remove
the warning with a code change.

This workaround in lib/librte_eal/common/eal_common_options.c
makes 200% sure the default_set is initialized:

-       if (pthread_getaffinity_np(pthread_self(), sizeof(rte_cpuset_t),
-                               &default_set))
-               CPU_ZERO(&default_set);
-
+       CPU_ZERO(&default_set);
+       pthread_getaffinity_np(pthread_self(),
+                       sizeof default_set, &default_set);