The makefile calls shaderwriter.py once for every shader, but on every call all shaders are processed by shaderwriter.py.
A good solutions would be to write all shaders to one header-file (instead of every shader to its own), say /src/shaders/shaders.h, and have this as a make-target (with all .glsl-files as prerequisites) which is necessary for the final build.
The makefile calls shaderwriter.py once for every shader, but on every call all shaders are processed by shaderwriter.py.
A good solutions would be to write all shaders to one header-file (instead of every shader to its own), say /src/shaders/shaders.h, and have this as a make-target (with all .glsl-files as prerequisites) which is necessary for the final build.