Index: llvm/trunk/lib/Fuzzer/build.sh
===================================================================
--- llvm/trunk/lib/Fuzzer/build.sh
+++ llvm/trunk/lib/Fuzzer/build.sh
@@ -1,7 +1,8 @@
 #!/bin/bash
 LIBFUZZER_SRC_DIR=$(dirname $0)
+CXX="${CXX:-clang}"
 for f in $LIBFUZZER_SRC_DIR/*.cpp; do
-  clang -g -O2 -fno-omit-frame-pointer -std=c++11 $f -c &
+  $CXX -g -O2 -fno-omit-frame-pointer -std=c++11 $f -c &
 done
 wait
 rm -f libFuzzer.a