Hi, Thomas Petazzoni wrote, > Hello, > > On Wed, 31 May 2017 23:41:26 +0000, Anthony G. Basile wrote: > > From: "Anthony G. Basile" <bluen...@gentoo.org> > > > > man feature_test_macros(7) specifies that _BSD_SOURCE and _SVID_SOURCE have > > been deprecated in favor of _DEFAULT_SOURCE since libc 2.20. Specifying > > either of the former is now equivalent to specifying just the latter. We > > add > > this macro to conform to this standard, but do not add the compiler warning > > to maintain full backwards compatibility with earlier version of glibc and > > uclibc. > > > > Signed-off-by: Anthony G. Basile <bluen...@gentoo.org> > > This patch breaks the build of the "knock" package in Buildroot: > > > http://autobuild.buildroot.net/results/908/90863b5adb769a346acd3dc4bbe8d5fa497a0581/build-end.log > > src/knockd.c:1296:37: error: 'struct tcphdr' has no member named 'th_flags' > > The tcphdr structure is defined in uClibc in two different ways, > depending on whether _FAVOR_BSD is defined or not. If _FAVOR_BSD is > defined, then the structure does have this th_flags member, otherwise > not. > > _FAVOR_BSD is defined as follows: > > #if defined _BSD_SOURCE && \ > !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ > defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \ > defined _GNU_SOURCE || defined _SVID_SOURCE) > # define __FAVOR_BSD 1 > #endif > > When being built, the program passes both -D_BSD_SOURCE and > -D_DEFAULT_SOURCE. However, this patch has the effect that defining > _DEFAULT_SOURCE defines _SVID_SOURCE, which has the side effect of no > longer defining _FAVOR_BSD. > > The definition of _DEFAULT_SOURCE is that it is equivalent to defining > _BSD_SOURCE and _SVID_SOURCE. However, it turns out that in the context > of uClibc, defining _SVID_SOURCE prevents __FAVOR_BSD from being > defined. > > Where is the bug? In what the knock build system is doing, or in uClibc?
As it seems to compile fine for glibc based toolchain, it is a regression in uClibc-ng. best regards Waldemar _______________________________________________ devel mailing list devel@uclibc-ng.org https://mailman.uclibc-ng.org/cgi-bin/mailman/listinfo/devel
