set library version in bazel (#1746)

* set library version in bazel

BUILD.bazel

@@ -51,6 +51,7 @@ cc_library(
     }),
     defines = [
         "BENCHMARK_STATIC_DEFINE",
+        "BENCHMARK_VERSION=\\\"" + (module_version() if module_version() != None else "") + "\\\"",
     ] + select({
         ":perfcounters": ["HAVE_LIBPFM"],
         "//conditions:default": [],

src/benchmark.cc

@@ -748,13 +748,7 @@ int InitializeStreams() {
 
 }  // end namespace internal
 
-std::string GetBenchmarkVersiom() {
-#if defined(BENCHMARK_VERSION)
-  return {BENCHMARK_VERSION};
-#else
-  return "hello, bazel!";
-#endif
-}
+std::string GetBenchmarkVersiom() { return {BENCHMARK_VERSION}; }
 
 void PrintDefaultHelp() {
   fprintf(stdout,