c++ link error if multiple files include header

if a project includes mraa.hpp in multiple source files, the build will
fail in link with multiple defines:
Blink-IO2.o: In function `mraa::getVersion()':
/usr/include/mraa/common.hpp:48: multiple definition of
`mraa::getVersion()'
Blink-IO.o:/usr/include/mraa/common.hpp:48: first defined here
Blink-IO2.o: In function `mraa::setPriority(unsigned int)':
/usr/include/mraa/common.hpp:64: multiple definition of
`mraa::setPriority(unsigned int)'
Blink-IO.o:/usr/include/mraa/common.hpp:64: first defined here
Blink-IO2.o: In function `mraa::getPlatformType()':
/usr/include/mraa/common.hpp:74: multiple definition of
`mraa::getPlatformType()'
Blink-IO.o:/usr/include/mraa/common.hpp:74: first defined here
Blink-IO2.o: In function `mraa::printError(mraa_result_t)':
/usr/include/mraa/common.hpp:84: multiple definition of
`mraa::printError(mraa_result_t)'
Blink-IO.o:/usr/include/mraa/common.hpp:84: first defined here
Blink-IO2.o: In function `mraa::pinModeTest(int, mraa_pinmodes_t)':
/usr/include/mraa/common.hpp:95: multiple definition of
`mraa::pinModeTest(int, mraa_pinmodes_t)'
Blink-IO.o:/usr/include/mraa/common.hpp:95: first defined here
Blink-IO2.o: In function `mraa::adcRawBits()':
/usr/include/mraa/common.hpp:106: multiple definition of
`mraa::adcRawBits()'
Blink-IO.o:/usr/include/mraa/common.hpp:106: first defined here
Blink-IO2.o: In function `mraa::adcSupportedBits()':
/usr/include/mraa/common.hpp:116: multiple definition of
`mraa::adcSupportedBits()'
Blink-IO.o:/usr/include/mraa/common.hpp:116: first defined here
Blink-IO2.o: In function `mraa::setLogLevel(int)':
/usr/include/mraa/common.hpp:127: multiple definition of
`mraa::setLogLevel(int)'
Blink-IO.o:/usr/include/mraa/common.hpp:127: first defined here
collect2: error: ld returned 1 exit status
makefile:53: recipe for target 'blinkio' failed
make: *** [blinkio] Error 1
Uart defines for Edison

Not sure if this one is 100% correct, but I know the call:
uart = mraa_uart_init(0);
fails as there are no objects defined...