make clean required before make

[jelber2]

Hi,

If I follow

git clone https://github.com/vpc-ccg/haslr.git
cd haslr
make

For commit e67b1eb

I get the following error

src/Assemble.cpp:6:20: fatal error: spoa.hpp: No such file or directory

Unless I do

make clean
make

Not a big issue, I am using gcc (Ubuntu 5.4.0-6ubuntu1~16.04.12) 5.4.0 20160609

Update: Actually I used make -j 75 and got the above error, but don't get that error if I use just plain make.