Enable race detection option

Build Tile38 with the Go race detector using the GORACE=1
environment variable, such as:

    GORACE=1 make

This is for debugging purposes only and shouldn't be used in
production.

Author: tidwall

scripts/build.sh

@@ -31,14 +31,9 @@ core/gen.sh
 LDFLAGS="$LDFLAGS -extldflags '-static'"
 export CGO_ENABLED=0
 
-# if [ "$NOMODULES" != "1" ]; then
-# 	export GO111MODULE=on
-# 	export GOFLAGS=-mod=vendor
-# 	go mod vendor
-# fi
-
 if [[ "$GORACE" == "1" ]]; then
-goflags="$goflags -race"
+	export CGO_ENABLED=1
+	goflags="$goflags -race"
 fi
 
 # Build and store objects into original directory.