When CFLAGS_EXTRA/LDFLAGS_EXTRA (or anything) is set on the command line of
a make invocation then it will completely override any setting or appending
of these variables in the makefile(s). This means builds like the coverage
variant will have their mpconfigvariant.mk settings overridden. Fix this
by using CFLAGS/LDFLAGS exclusively in the makefile(s), reserving the
CFLAGS_EXTRA/LDFLAGS_EXTRA variables for external command-line use only.
Invoking "make" will still build the standard "micropython" executable, but
other variants are now build using, eg, "make VARIANT=minimal". This
follows how bare-metal ports specify a particular board, and allows running
any make target (eg clean, test) with any variant.
Convenience targets (eg "make coverage") are provided to retain the old
behaviour, at least for now.
See issue #3043.
Scott Shawcroft
Damien George
Damien George
Jim Mussared