CMakeLists.txt: fix static build with libusb and -latomic

Use pkg-config to retrieve libusb dependencies such as -latomic and
avoid the following static build failure:

/nvmedata/autobuild/instance-29/output-1/per-package/libftdi1/host/bin/../lib/gcc/sparc-buildroot-linux-uclibc/10.3.0/../../../../sparc-buildroot-linux-uclibc/bin/ld: /nvmedata/autobuild/instance-29/output-1/per-package/libftdi1/host/sparc-buildroot-linux-uclibc/sysroot/lib/libusb-1.0.a(core.o): in function `libusb_unref_device':
/nvmedata/autobuild/instance-29/output-1/build/libusb-1.0.25/libusb/core.c:1186: undefined reference to `__atomic_fetch_add_4'

Fixes:
 - http://autobuild.buildroot.org/results/1ca7cd85ae60ad4797a6d8a83b2fb51d7eab96d9

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 58f664a..d20aa94 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,8 +25,16 @@ if(${CMAKE_BUILD_TYPE} STREQUAL Debug)
 endif(${CMAKE_BUILD_TYPE} STREQUAL Debug)
 
 # find libusb
-find_package ( USB1 REQUIRED )
-include_directories ( ${LIBUSB_INCLUDE_DIR} )
+find_package( PkgConfig )
+if (PkgConfig_FOUND)
+  pkg_check_modules( LIBUSB libusb-1.0 )
+  if (LIBUSB_FOUND)
+    include_directories ( ${LIBUSB_INCLUDE_DIRS} )
+  else()
+    find_package ( USB1 REQUIRED )
+    include_directories ( ${LIBUSB_INCLUDE_DIR} )
+  endif()
+endif()
 
 # Find Boost
 if (FTDIPP OR BUILD_TESTS)