replace non portable echo -n with printf
@@ -573,7 +573,7 @@ source-only: all
%.8: %
@echo .TH $* 8 $(BUILD_DATE) "afl++" > $@
@echo .SH NAME >> $@
- @echo -n ".B $* \- " >> $@
+ @printf "%s" ".B $* \- " >> $@
@./$* -h 2>&1 | head -n 1 | sed -e "s/$$(printf '\e')[^m]*m//g" >> $@
@echo >> $@
@echo .SH SYNOPSIS >> $@
