build: add V8 embedder version string

After this commit, `process.versions.v8` will look like:
"6.0.287.53-node.0".
The goal is that everytime we apply a non-official patch to `deps/v8`,
we increment our own number instead of V8's patch level.
This number must be set back to 0 after major V8 updates.

Fixes: https://github.com/nodejs/node/issues/15698
PR-URL: https://github.com/nodejs/node/pull/15785
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>

1 files changed, 7 insertions, 5 deletions

diff --git a/lib/internal/v8_prof_polyfill.js b/lib/internal/v8_prof_polyfill.js
index e77f1f76bcb..1c9ba4ebc54 100644
--- a/lib/internal/v8_prof_polyfill.js
+++ b/lib/internal/v8_prof_polyfill.js
@@ -82,14 +82,16 @@ function readline() {
 }
 
 function versionCheck() {
-  // v8-version looks like "v8-version,$major,$minor,$build,$patch,$candidate"
-  // whereas process.versions.v8 is either "$major.$minor.$build" or
-  // "$major.$minor.$build.$patch".
+  // v8-version looks like
+  // "v8-version,$major,$minor,$build,$patch[,$embedder],$candidate"
+  // whereas process.versions.v8 is either "$major.$minor.$build-$embedder" or
+  // "$major.$minor.$build.$patch-$embedder".
   var firstLine = readline();
   line = firstLine + '\n' + line;
   firstLine = firstLine.split(',');
-  const curVer = process.versions.v8.split('.');
-  if (firstLine.length !== 6 && firstLine[0] !== 'v8-version') {
+  const curVer = process.versions.v8.split(/\.-/);
+  if (firstLine.length !== 6 && firstLine.length !== 7 ||
+      firstLine[0] !== 'v8-version') {
     console.log('Unable to read v8-version from log file.');
     return;
   }