[dpdk-dev] [PATCH v2 1/7] linuxapp: build with _GNU_SOURCE defined by default

[Anatoly Burakov <anatoly.burakov@intel.com>]

We use _GNU_SOURCE all over the place, but often times we miss
defining it, resulting in broken builds on musl. Rather than
fixing every library's and driver's and application's makefile,
fix it by simply defining _GNU_SOURCE by default for all
Linuxapp builds.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 app/meson.build                      |  9 ++++++++-
 drivers/bus/pci/linux/Makefile       |  2 --
 drivers/meson.build                  |  6 ++++++
 drivers/net/softnic/conn.c           |  1 -
 examples/meson.build                 |  6 ++++++
 lib/librte_eal/linuxapp/eal/Makefile | 16 ----------------
 lib/meson.build                      |  6 ++++++
 mk/exec-env/linuxapp/rte.vars.mk     |  2 ++
 test/test/meson.build                |  5 +++++
 9 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/app/meson.build b/app/meson.build
index 99e0b93ec..c9a52a22b 100644
--- a/app/meson.build
+++ b/app/meson.build
@@ -11,13 +11,20 @@ apps = ['pdump',
 # for BSD only
 lib_execinfo = cc.find_library('execinfo', required: false)
 
+default_cflags = machine_args
+
+# on Linux, specify -D_GNU_SOURCE unconditionally
+if host_machine.system() == 'linux'
+	default_cflags += '-D_GNU_SOURCE'
+endif
+
 foreach app:apps
 	build = true
 	name = app
 	allow_experimental_apis = false
 	sources = []
 	includes = []
-	cflags = machine_args
+	cflags = default_cflags
 	objs = [] # other object files to link against, used e.g. for
 	          # instruction-set optimized versions of code
 
diff --git a/drivers/bus/pci/linux/Makefile b/drivers/bus/pci/linux/Makefile
index 96ea1d540..90404468b 100644
--- a/drivers/bus/pci/linux/Makefile
+++ b/drivers/bus/pci/linux/Makefile
@@ -4,5 +4,3 @@
 SRCS += pci.c
 SRCS += pci_uio.c
 SRCS += pci_vfio.c
-
-CFLAGS += -D_GNU_SOURCE
diff --git a/drivers/meson.build b/drivers/meson.build
index 47b4215a3..74fec716d 100644
--- a/drivers/meson.build
+++ b/drivers/meson.build
@@ -16,6 +16,12 @@ default_cflags = machine_args
 if cc.has_argument('-Wno-format-truncation')
 	default_cflags += '-Wno-format-truncation'
 endif
+
+# on Linux, specify -D_GNU_SOURCE unconditionally
+if host_machine.system() == 'linux'
+	default_cflags += '-D_GNU_SOURCE'
+endif
+
 foreach class:driver_classes
 	drivers = []
 	std_deps = []
diff --git a/drivers/net/softnic/conn.c b/drivers/net/softnic/conn.c
index 990cf40fc..8b6658088 100644
--- a/drivers/net/softnic/conn.c
+++ b/drivers/net/softnic/conn.c
@@ -8,7 +8,6 @@
 #include <unistd.h>
 #include <sys/types.h>
 
-#define __USE_GNU
 #include <sys/socket.h>
 
 #include <sys/epoll.h>
diff --git a/examples/meson.build b/examples/meson.build
index 4ee7a1114..70c22eb62 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -22,6 +22,12 @@ default_cflags = machine_args
 if cc.has_argument('-Wno-format-truncation')
 	default_cflags += '-Wno-format-truncation'
 endif
+
+# on Linux, specify -D_GNU_SOURCE unconditionally
+if host_machine.system() == 'linux'
+	default_cflags += '-D_GNU_SOURCE'
+endif
+
 foreach example: examples
 	name = example
 	build = true
diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index fd92c75c2..bfee453bc 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -85,22 +85,6 @@ SRCS-y += rte_cycles.c
 
 CFLAGS_eal_common_cpuflags.o := $(CPUFLAGS_LIST)
 
-CFLAGS_eal.o := -D_GNU_SOURCE
-CFLAGS_eal_interrupts.o := -D_GNU_SOURCE
-CFLAGS_eal_vfio_mp_sync.o := -D_GNU_SOURCE
-CFLAGS_eal_timer.o := -D_GNU_SOURCE
-CFLAGS_eal_lcore.o := -D_GNU_SOURCE
-CFLAGS_eal_memalloc.o := -D_GNU_SOURCE
-CFLAGS_eal_thread.o := -D_GNU_SOURCE
-CFLAGS_eal_log.o := -D_GNU_SOURCE
-CFLAGS_eal_common_log.o := -D_GNU_SOURCE
-CFLAGS_eal_hugepage_info.o := -D_GNU_SOURCE
-CFLAGS_eal_common_whitelist.o := -D_GNU_SOURCE
-CFLAGS_eal_common_options.o := -D_GNU_SOURCE
-CFLAGS_eal_common_thread.o := -D_GNU_SOURCE
-CFLAGS_eal_common_lcore.o := -D_GNU_SOURCE
-CFLAGS_rte_cycles.o := -D_GNU_SOURCE
-
 # workaround for a gcc bug with noreturn attribute
 # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12603
 ifeq ($(CONFIG_RTE_TOOLCHAIN_GCC),y)
diff --git a/lib/meson.build b/lib/meson.build
index 3acc67e6e..2c7ea436a 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -32,6 +32,12 @@ if cc.has_argument('-Wno-format-truncation')
 endif
 
 enabled_libs = [] # used to print summary at the end
+
+# on Linux, specify -D_GNU_SOURCE unconditionally
+if host_machine.system() == 'linux'
+	default_cflags += '-D_GNU_SOURCE'
+endif
+
 foreach l:libraries
 	build = true
 	name = l
diff --git a/mk/exec-env/linuxapp/rte.vars.mk b/mk/exec-env/linuxapp/rte.vars.mk
index 3129edc8c..91b778fcc 100644
--- a/mk/exec-env/linuxapp/rte.vars.mk
+++ b/mk/exec-env/linuxapp/rte.vars.mk
@@ -17,6 +17,8 @@ else
 EXECENV_CFLAGS  = -pthread
 endif
 
+EXECENV_CFLAGS += -D_GNU_SOURCE
+
 EXECENV_LDLIBS  =
 EXECENV_ASFLAGS =
 
diff --git a/test/test/meson.build b/test/test/meson.build
index b1dd6eca2..c81fca439 100644
--- a/test/test/meson.build
+++ b/test/test/meson.build
@@ -242,6 +242,11 @@ if cc.has_argument('-Wno-format-truncation')
     cflags += '-Wno-format-truncation'
 endif
 
+# on Linux, specify -D_GNU_SOURCE unconditionally
+if host_machine.system() == 'linux'
+	default_cflags += '-D_GNU_SOURCE'
+endif
+
 test_dep_objs = []
 compress_test_dep = dependency('zlib', required: false)
 if compress_test_dep.found()
-- 
2.17.1