Two things kept every register-driven module out of the host harness. The
SFR keywords were unknown, so rtl837x_sfr.h did not compile at all, and once
it did, each translation unit would have defined its own copy of the
registers. They map to extern declarations now; a mock emits the storage
once by re-including the header with the keywords redefined.
The other was memset. rtl837x_common.h hides the firmware's own prototypes
under RTLP_HOST_TEST so host builds use the C library, but nothing declared
the library versions, and the modules do call them. The shim pulls in
string.h ahead of everything, where nothing can clash with it.
Building the firmware headers on the host showed two warnings from
machine.h: `typedef struct machine { ... };` and the same for
machine_runtime declare no alias, so the keyword only draws "useless
storage class specifier in empty declaration". Every user says
`struct machine`, so drop the keyword.
-Wno-builtin-declaration-mismatch is a gcc switch and clang reports it
as an unknown option on every build; add it only when the compiler is
not clang.
Compile selected firmware translation units unmodified under host gcc with
AddressSanitizer and UBSan, force-including a shim header that erases the
SDCC 8051 keywords, and link them against a mocked serial ring and console.
A first suite covers the CLI line editor: line entry, backspace editing,
and both long-input overflow cases (length cap and ring-pointer stall).
The only firmware-source change is one #ifndef RTLP_HOST_TEST block in
rtl837x_common.h grouping the libc-named prototypes (sleep/memcpy/memset/
strlen/strcpy/strcmp) so host builds take them from the C library instead;
on-target builds are unaffected.
Run with: make -C test