[dpdk-dev] [PATCH v2 7/7] build/pkg-config: prevent overlinking

[Bruce Richardson <bruce.richardson@intel.com>]

Add the --as-needed linker flag to the DPDK library list in the pkg-config
file so as to prevent overlinking. Without this flag, when linking
statically using flags from $(pkg-config --static --libs libdpdk), all DPDK
drivers and libs were statically linked in, but the binary was also
requiring all the shared versions be present to run.

The real root-cause of this issue is that the DPDK libraries need to be
duplicated in the linker command when doing static linking, due to the
behaviour of pkg-config, but since that behaviour cannot be easily changed,
this is a simple workaround to avoid problems.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
V2: expand commit log to explain that pkg-config behaviour of part of the
problem.
---
 buildtools/pkg-config/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/buildtools/pkg-config/meson.build b/buildtools/pkg-config/meson.build
index e043c5ee1..5c1e31c4d 100644
--- a/buildtools/pkg-config/meson.build
+++ b/buildtools/pkg-config/meson.build
@@ -23,7 +23,7 @@ Use libdpdk.pc instead of this file to query DPDK compile/link arguments''',
 	version: meson.project_version(),
 	subdirs: [get_option('include_subdir_arch'), '.'],
 	extra_cflags: pkg_extra_cflags,
-	libraries: dpdk_libraries,
+	libraries: ['-Wl,--as-needed'] + dpdk_libraries,
 	libraries_private: dpdk_extra_ldflags)
 
 pkg.generate(name: 'DPDK', # main DPDK pkgconfig file
-- 
2.20.1