add test to check if argp is available or not. Update README

CMakeLists.txt

@@ -19,6 +19,15 @@ pkg_check_modules(LIBFTDIPP REQUIRED libftdipp1)
 pkg_check_modules(LIBUSB REQUIRED libusb-1.0)
 pkg_check_modules(LIBUDEV REQUIRED libudev)
 
+# for non glibc, argp-standalone is required and must be
+# explicitly linked. This code will fail for others libc
+# implementations
+include(CheckCXXSourceCompiles)
+check_cxx_source_compiles("
+	#include <argp.h>
+	int main(int argc, char **argv) {
+	argp_parse(NULL, argc, argv, 0, 0, NULL);}" HAVE_ARGP)
+
 set(OPENFPGALOADER_SOURCE
 	src/spiFlash.cpp
 	src/epcq.cpp
@@ -90,6 +99,10 @@ target_link_libraries(openFPGALoader
 	${LIBFTDIPP_LIBRARIES}
 )
 
+if(NOT HAVE_ARGP)
+	target_link_libraries(openFPGALoader /usr/lib/libargp.a)
+endif()
+
 # libftdi < 1.4 as no usb_addr
 if (${LIBFTDI_VERSION} VERSION_LESS 1.4)
 	set(CMAKE_CXX_FLAGS "-DOLD_FTDI_VERSION=1")

README.md

@@ -36,7 +36,11 @@ depending of the distribution, headers too)
 ```bash
 apt-get install libftdi1-2 libftdi1-dev libftdipp1-3 libftdipp1-dev libudev-dev cmake
 ```
-and if not already done, install **pkg-config**, **make** and **g++**.
+
+For distributions using non-glibc (musl, uClibc) **argp-standalone** must be
+installed.
+
+And if not already done, install **pkg-config**, **make** and **g++**.
 
 To build the app:
 ```bash