Fix cmake version detection from git tag.

CMakeLists.txt

@@ -244,7 +244,7 @@ endif()
 
 # version info from git
 execute_process(
-	COMMAND Tools/tag_to_version.py ${PX4_SOURCE_DIR}
+	COMMAND Tools/tag_to_version.py --root ${PX4_SOURCE_DIR}
 	OUTPUT_VARIABLE version
 	WORKING_DIRECTORY ${PX4_SOURCE_DIR}
 	)
@@ -255,7 +255,7 @@ execute_process(
 	WORKING_DIRECTORY ${PX4_SOURCE_DIR}
 	)
 set(package-contact "px4users@googlegroups.com")
-message(STATUS "PX4 VERSION: ${version}")
+message(STATUS "VERSION: ${version}")
 
 #=============================================================================
 # find programs and packages

Tools/tag_to_version.py

+import subprocess
+import os
+import argparse
+
+p = argparse.ArgumentParser('finds major minor patch version from git tag')
+p.add_argument('--root', help="root of git repo", default=".")
+args = p.parse_args()
+os.chdir(args.root)
+p= subprocess.Popen(
+    'git describe --always --tags'.split(),
+    stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+stdout, stderr = p.communicate()
+res = stdout.split('-')[0].split('.')
+major = res[0].replace('v','')
+minor = res[1]
+patch = res[2]
+print("{:s}.{:s}.{:s}".format(major, minor, patch))