diff --git a/src/files.c b/src/files.c
index 0ef6e9c..a78d4f5 100644
--- a/src/files.c
+++ b/src/files.c
@@ -552,6 +552,12 @@ pkgdatadir (void)
     return relocate_buffer;
   else
     {
+      char *bazel_runfiles_bison_pkgdatadir();
+      static char *bazel_pkgdatadir_p = NULL;
+      if (bazel_pkgdatadir_p == NULL) {
+        bazel_pkgdatadir_p = bazel_runfiles_bison_pkgdatadir();
+      }
+      if (bazel_pkgdatadir_p != NULL) { return bazel_pkgdatadir_p; }
       char const *cp = getenv ("BISON_PKGDATADIR");
       return cp ? cp : relocate2 (PKGDATADIR, &relocate_buffer);
     }
@@ -560,7 +566,13 @@ pkgdatadir (void)
 char const *
 m4path (void)
 {
-  char const *m4 = getenv ("M4");
+  char *bazel_runfiles_m4();
+  static char *bazel_m4_p = NULL;
+  if (bazel_m4_p == NULL) {
+    bazel_m4_p = bazel_runfiles_m4();
+  }
+
+  char const *m4 = bazel_m4_p? bazel_m4_p : (m4 = getenv ("M4")) ? m4 : M4;
   if (m4)
     return m4;
 
diff --git a/src/main.c b/src/main.c
index 1185bf2..c0ae4a6 100644
--- a/src/main.c
+++ b/src/main.c
@@ -63,6 +63,8 @@
 int
 main (int argc, char *argv[])
 {
+  void bazel_runfiles_init(const char *argv0);
+  bazel_runfiles_init(argv[0]);
   {
     char *cp = getenv ("BISON_PROGRAM_NAME");
     if (cp)