[dpdk-stable] [PATCH 18.11 1/1] build: enable BSD features visibility for FreeBSD

[Kevin Traynor <ktraynor@redhat.com>]

From: Marcin Smoczynski <marcinx.smoczynski@intel.com>

[ upstream commit 28188cee2aa0b72d401d3e56942d0db9c7b9e654]

When a component uses either XOPEN_SOURCE or POSIX_C_SOURCE macro
explicitly in its build recipe, it restricts visibility of a non POSIX
features subset, such as IANA protocol numbers (IPPROTO_* macros).
Non standard features are enabled by default for DPDK both for Linux
thanks to _GNU_SOURCE and for FreeBSD thanks to __BSD_VISIBLE. However
using XOPEN_SOURCE or POSIX_(C_)SOURCE in a component causes
__BSD_VISIBLE to be defined to 0 for FreeBSD, causing different feature
sets visibility for Linux and FreeBSD. It restricts from using IPPROTO
macros in public headers, such as rte_ip.h, despite the fact they are
already widely used in sources.

Add __BSD_VISIBLE macro specified unconditionally for FreeBSD targets
which enforces feature sets visibility unification between Linux and
FreeBSD.

Add single -D_GNU_SOURCE to config/meson.build as a project argument
instead of adding separate directive for each project subtree.

This patch solves the problem of build breaks for [1] on FreeBSD [2]
following the discussion [3].

[1] https://mails.dpdk.org/archives/dev/2019-May/131885.html
[2] http://mails.dpdk.org/archives/test-report/2019-May/082263.html
[3] https://mails.dpdk.org/archives/dev/2019-May/132110.html

[18.11]
The following 18.11 branch commit needs __BSD_VISIBLE to be defined,
so backporting this commit to 18.11 branch.

Fixes: 54e4657b2385 ("net: define IPv4 IHL and VHL")

Signed-off-by: Marcin Smoczynski <marcinx.smoczynski@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
---
 app/meson.build               | 3 ---
 config/meson.build            | 8 ++++++++
 drivers/meson.build           | 3 ---
 examples/meson.build          | 3 ---
 lib/meson.build               | 3 ---
 meson.build                   | 6 +++++-
 mk/target/generic/rte.vars.mk | 5 +++++
 7 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/app/meson.build b/app/meson.build
index a9a026bbf..fd5f701b3 100644
--- a/app/meson.build
+++ b/app/meson.build
@@ -14,7 +14,4 @@ lib_execinfo = cc.find_library('execinfo', required: false)
 default_cflags = machine_args
 
-# specify -D_GNU_SOURCE unconditionally
-default_cflags += '-D_GNU_SOURCE'
-
 foreach app:apps
 	build = true
diff --git a/config/meson.build b/config/meson.build
index 80d253828..fd263b848 100644
--- a/config/meson.build
+++ b/config/meson.build
@@ -136,2 +136,10 @@ install_headers('rte_config.h', subdir: get_option('include_subdir_arch'))
 # enable VFIO only if it is linux OS
 dpdk_conf.set('RTE_EAL_VFIO', host_machine.system() == 'linux')
+
+# specify -D_GNU_SOURCE unconditionally
+add_project_arguments('-D_GNU_SOURCE', language: 'c')
+
+# specify -D__BSD_VISIBLE for FreeBSD
+if host_machine.system() == 'freebsd'
+	add_project_arguments('-D__BSD_VISIBLE', language: 'c')
+endif
diff --git a/drivers/meson.build b/drivers/meson.build
index c3c66bbc0..f965c33e7 100644
--- a/drivers/meson.build
+++ b/drivers/meson.build
@@ -18,7 +18,4 @@ if cc.has_argument('-Wno-format-truncation')
 endif
 
-# specify -D_GNU_SOURCE unconditionally
-default_cflags += '-D_GNU_SOURCE'
-
 foreach class:driver_classes
 	drivers = []
diff --git a/examples/meson.build b/examples/meson.build
index af81c762e..2809e2261 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -24,7 +24,4 @@ if cc.has_argument('-Wno-format-truncation')
 endif
 
-# specify -D_GNU_SOURCE unconditionally
-default_cflags += '-D_GNU_SOURCE'
-
 foreach example: examples
 	name = example
diff --git a/lib/meson.build b/lib/meson.build
index df4226c51..62b5cdfe8 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -35,7 +35,4 @@ endif
 enabled_libs = [] # used to print summary at the end
 
-# -D_GNU_SOURCE unconditionally
-default_cflags += '-D_GNU_SOURCE'
-
 foreach l:libraries
 	build = true
diff --git a/meson.build b/meson.build
index abe76f7b7..beb599d2f 100644
--- a/meson.build
+++ b/meson.build
@@ -71,4 +71,8 @@ dpdk_drivers = ['-Wl,--whole-archive'] + dpdk_drivers + ['-Wl,--no-whole-archive
 
 pkg = import('pkgconfig')
+pkg_extra_cflags = ['-include', 'rte_config.h'] + machine_args
+if host_machine.system() == 'freebsd'
+	pkg_extra_cflags += ['-D__BSD_VISIBLE']
+endif
 pkg.generate(name: meson.project_name(),
 	filebase: 'lib' + meson.project_name().to_lower(),
@@ -81,5 +85,5 @@ Note that CFLAGS might contain an -march flag higher than typical baseline.
 This is required for a number of static inline functions in the public headers.''',
 	subdirs: [get_option('include_subdir_arch'), '.'],
-	extra_cflags: ['-include', 'rte_config.h'] + machine_args
+	extra_cflags: pkg_extra_cflags
 )
 
diff --git a/mk/target/generic/rte.vars.mk b/mk/target/generic/rte.vars.mk
index dd149acc9..ca38d4181 100644
--- a/mk/target/generic/rte.vars.mk
+++ b/mk/target/generic/rte.vars.mk
@@ -112,4 +112,9 @@ endif
 CFLAGS += -D_GNU_SOURCE
 
+# define __BSD_VISIBLE when building for FreeBSD
+ifeq ($(CONFIG_RTE_EXEC_ENV_FREEBSD),y)
+CFLAGS += -D__BSD_VISIBLE
+endif
+
 export CFLAGS
 export LDFLAGS
-- 
2.20.1