Makefile: Use more variables to hold compiler flags
Enclose shell variables in quotes
Find missing preload libraries on non-english locales
Don't preload in subshell
Big overhaul

- Use constructor function attributes to find the originals of
   replaced symbols.
- Place scaffolding and support code in separate file(s).
- Measure clock ticks from (arbitrary) initial value.
- Write RIFF header for WAVE data.
- Provide wave data target as path or file descriptor number.
- Provide macros for wave generation parameters for easier
   customisation (e. g. by non-programmers).
QtCreator project