contrib/fuzz/Makefile

run-tests: cache hghave results

Spawning a process on Windows is expensive.  I've got a version of
test-lfs-test-server.t locally which prints the http request/responses that
totals 819 lines, with 149 conditional lines, 11 #if tests, and 2 test cases.
It takes just under 1 minute with this change to run both cases, vs just over
2 minutes without this change.  Worse, when I explored adding ui.debug to the
test, it takes 13 minutes due to all of the mismatches and retests, vs less than
1 minute with this change.  Overall, the difference when running all tests is
negligible- 103 minutes with this change, vs 105 without when using -j9.

It also looks like an exit value of 2 from `hghave` is treated specially, but
there's nothing preventing 2 missing features from also using this value.

bdiff.o: ../../mercurial/bdiff.c
	clang -g -O1 -fsanitize=fuzzer-no-link,address -c -o bdiff.o \
	  ../../mercurial/bdiff.c

bdiff: bdiff.cc bdiff.o
	clang -DHG_FUZZER_INCLUDE_MAIN=1 -g -O1 -fsanitize=fuzzer-no-link,address \
	  -I../../mercurial bdiff.cc bdiff.o -o bdiff

bdiff-oss-fuzz.o: ../../mercurial/bdiff.c
	$$CC $$CFLAGS -c -o bdiff-oss-fuzz.o ../../mercurial/bdiff.c

bdiff_fuzzer: bdiff.cc bdiff-oss-fuzz.o
	$$CXX $$CXXFLAGS -std=c++11 -I../../mercurial bdiff.cc \
	  bdiff-oss-fuzz.o -lFuzzingEngine -o $$OUT/bdiff_fuzzer

all: bdiff

oss-fuzz: bdiff_fuzzer

.PHONY: all oss-fuzz