[infra] Golang coverage summary for each fuzz target (#2817, #2714). (#4671)

* Golang coverage summary for each fuzz target

* Document usage of compile_go_fuzzer

* update the documentation change

Co-authored-by: Max Moroz <mmoroz@chromium.org>

1 files changed, 11 insertions, 14 deletions

diff --git a/docs/getting-started/new-project-guide/go_lang.md b/docs/getting-started/new-project-guide/go_lang.md
index be7482c33..94ab41707 100644
--- a/docs/getting-started/new-project-guide/go_lang.md
+++ b/docs/getting-started/new-project-guide/go_lang.md
@@ -74,21 +74,18 @@ RUN go get github.com/ianlancetaylor/demangle
 In order to build a Go fuzz target, you need to call `go-fuzz`
 command first, and then link the resulting `.a` file against
 `$LIB_FUZZING_ENGINE` using the `$CXX $CXXFLAGS ...` command.
-[Example](https://github.com/google/oss-fuzz/blob/356f2b947670b7eb33a1f535c71bc5c87a60b0d1/projects/syzkaller/build.sh#L19):
 
-```sh
-function compile_fuzzer {
-  path=$1
-  function=$2
-  fuzzer=$3
-
-  # Compile and instrument all Go files relevant to this fuzz target.
-  go-fuzz -func $function -o $fuzzer.a $path
+The best way to do this is by using a `compile_go_fuzzer` script,
+as it also supports coverage builds.
 
-  # Link Go code ($fuzzer.a) with fuzzing engine to produce fuzz target binary.
-  $CXX $CXXFLAGS $LIB_FUZZING_ENGINE $fuzzer.a -o $OUT/$fuzzer
-}
+A usage example from go-dns project is
 
-compile_fuzzer ./pkg/compiler Fuzz compiler_fuzzer
-compile_fuzzer ./prog/test FuzzDeserialize prog_deserialize_fuzzer
+```sh
+compile_go_fuzzer github.com/miekg/dns FuzzNewRR fuzz_newrr fuzz
 ```
+
+Arguments are :
+* path of the package with the fuzz target
+* name of the fuzz function
+* name of the fuzzer to be built
+* optional tag to be used by `go build` and such