Re: [PATCH v2 1/2] Add libfuzzer target to fuzz/x86_instruction_emulator

[Tamas K Lengyel <tamas@xxxxxxxxxxxxx>]

On Mon, Jul 22, 2024 at 5:20 AM Jan Beulich <jbeulich@xxxxxxxx> wrote:
>
> On 26.06.2024 00:47, Tamas K Lengyel wrote:
> > This target enables integration into oss-fuzz. Changing invalid input return
> > to -1 as values other then 0/-1 are reserved by libfuzzer. Also adding the
> > missing __wrap_vsnprintf wrapper which is required for successful oss-fuzz
> > build.
> >
> > Signed-off-by: Tamas K Lengyel <tamas@xxxxxxxxxxxxx>
>
> I've reverted this right away, because of ...
>
> > @@ -58,6 +58,9 @@ afl-harness: afl-harness.o $(OBJS) cpuid.o wrappers.o
> >  afl-harness-cov: afl-harness-cov.o $(patsubst %.o,%-cov.o,$(OBJS)) cpuid.o 
> > wrappers.o
> >       $(CC) $(CFLAGS) $(GCOV_FLAGS) $(addprefix 
> > -Wl$(comma)--wrap=,$(WRAPPED)) $^ -o $@
> >
> > +libfuzzer-harness: $(OBJS) cpuid.o wrappers.o
> > +     $(CC) $(CFLAGS) $(LIB_FUZZING_ENGINE) -fsanitize=fuzzer $(addprefix 
> > -Wl$(comma)--wrap=,$(WRAPPED)) $^ -o $@
>
> ... this causing
>
> gcc: error: unrecognized argument to '-fsanitize=' option: 'fuzzer'
> make[6]: *** [Makefile:62: libfuzzer-harness] Error 1
>
> with apparently a fair set of gcc-s used by distro-s we use for CI.

Well let me see if I can hack the Makefile to only build this with clang..

Tamas