Code review markups:

- Correct use of CPPFLAGS
- Detect allocation failure
- Add a CHECK macro for failure

3 files changed, 18 insertions, 17 deletions

diff --git a/ossfuzz/Makefile b/ossfuzz/Makefile
index 94829b2..2a7e439 100644
--- a/ossfuzz/Makefile
+++ b/ossfuzz/Makefile
@@ -30,9 +30,9 @@ LIB_FUZZING_ENGINE ?= standaloneengine.o
 DEBUGLEVEL?= 1
 DEBUGFLAGS = -g -DLZ4_DEBUG=$(DEBUGLEVEL)
 
-CFLAGS  += -I$(LZ4DIR) $(DEBUGFLAGS) $(MOREFLAGS)
-CPPFLAGS+= -I$(LZ4DIR) -DXXH_NAMESPACE=LZ4_
-FLAGS    = $(CFLAGS) $(CPPFLAGS) $(LDFLAGS)
+CFLAGS   += -I$(LZ4DIR) $(DEBUGFLAGS) $(MOREFLAGS)
+CXXFLAGS += -I$(LZ4DIR) $(DEBUGFLAGS) $(MOREFLAGS)
+CPPFLAGS += -DXXH_NAMESPACE=LZ4_
 
 include ../Makefile.inc
 
@@ -42,13 +42,13 @@ $(LZ4DIR)/liblz4.a:
 	$(MAKE) -C $(LZ4DIR) CFLAGS="$(CFLAGS)" liblz4.a
 
 %.o: %.cc
-	$(CXX) -c $(CFLAGS) $(CPPFLAGS) $< -o $@
+	$(CXX) -c $(CXXFLAGS) $(CPPFLAGS) $< -o $@
 
 .PHONY: compress_fuzzer
 compress_fuzzer: compress_fuzzer.o $(LZ4DIR)/liblz4.a
 	# Compile the standalone code just in case. The OSS-Fuzz code might
 	# override the LIB_FUZZING_ENGINE value to "-fsanitize=fuzzer"
-	$(CXX) -c $(CFLAGS) $(CPPFLAGS) standaloneengine.cc -o standaloneengine.o
+	$(CXX) -c $(CXXFLAGS) $(CPPFLAGS) standaloneengine.cc -o standaloneengine.o
 
 	# Now compile the actual fuzzer.
-	$(CXX) $(FLAGS) $(LIB_FUZZING_ENGINE) $^ -o $@$(EXT)
+	$(CXX) $(CXXFLAGS) $(CPPFLAGS) $(LDFLAGS) $(LIB_FUZZING_ENGINE) $^ -o $@$(EXT)
diff --git a/ossfuzz/compress_fuzzer.cc b/ossfuzz/compress_fuzzer.cc
index 006a0ab..4a720e2 100644
--- a/ossfuzz/compress_fuzzer.cc
+++ b/ossfuzz/compress_fuzzer.cc
@@ -3,20 +3,24 @@
 #include <stdlib.h>
 #include "lz4.h"
 
+#define CHECK(COND)   if (!(COND)) { abort(); }
+
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
   size_t const compressed_dest_size = LZ4_compressBound(size);
   char *const dest_buffer = (char *)malloc(compressed_dest_size);
 
-  int result = LZ4_compress_default((const char*)data, dest_buffer,
-                                    size, compressed_dest_size);
-
-  if (result == 0)
+  if (dest_buffer != NULL)
   {
-    abort();
-  }
+    // Allocation succeeded, try compressing the incoming data.
+    int result = LZ4_compress_default((const char*)data,
+                                      dest_buffer,
+                                      size,
+                                      compressed_dest_size);
+    CHECK(result != 0);
 
-  free(dest_buffer);
+    free(dest_buffer);
+  }
 
   return 0;
 }
diff --git a/ossfuzz/ossfuzz.sh b/ossfuzz/ossfuzz.sh
index e0cb63c..87bc213 100755
--- a/ossfuzz/ossfuzz.sh
+++ b/ossfuzz/ossfuzz.sh
@@ -6,14 +6,11 @@
 # Save off the current folder as the build root.
 export BUILD_ROOT=$PWD
 
-# lz4 uses CPPFLAGS rather than CXX flags.
-export CPPFLAGS="${CXXFLAGS}"
-
 echo "CC: $CC"
 echo "CXX: $CXX"
 echo "LIB_FUZZING_ENGINE: $LIB_FUZZING_ENGINE"
 echo "CFLAGS: $CFLAGS"
-echo "CPPFLAGS: $CPPFLAGS"
+echo "CXXFLAGS: $CXXFLAGS"
 echo "OUT: $OUT"
 
 export MAKEFLAGS+="-j$(nproc)"