If you try to use cuda with gcc 5.0.3 according on Ubuntu 16.4 you might have the following problem:

Makefile:586: die Regel für Ziel „.build_release/cuda/src/caffe/layers/sigmoid_layer.o“ scheiterte
make: *** [.build_release/cuda/src/caffe/layers/sigmoid_layer.o] Fehler 1
/usr/include/string.h: In function ‘void* __mempcpy_inline(void*, const void*, size_t)’:
/usr/include/string.h:652:42: error: ‘memcpy’ was not declared in this scope
 return (char *) memcpy (__dest, __src, __n) + __n;

To solve this add -D_FORCE_INLINES to the following line in the Makefile:

COMMON_FLAGS += -DCAFFE_VERSION=$(DYNAMIC_VERSION_MAJOR).$(DYNAMIC_VERSION_MINOR).$(DYNAMIC_VERSION_REVISION)

The result should be:

COMMON_FLAGS += -DCAFFE_VERSION=$(DYNAMIC_VERSION_MAJOR).$(DYNAMIC_VERSION_MINOR).$(DYNAMIC_VERSION_REVISION) -D_FORCE_INLINES