From f3922da41459fcdb6f590abc29cc706bd397a4e1 Mon Sep 17 00:00:00 2001
From: Richard Lau <richard.lau@ibm.com>
Date: Fri, 30 Oct 2026 18:08:34 +0000
Subject: [PATCH] build: only set `V8_EMBEDDER_STRING` where needed

Passing `V8_EMBEDDER_STRING` on the command line to every compilation
unit invalidates the ccache for those sources when `v8_embedder_string`
is bumped in `common.gypi` meaning that almost all of `deps/v8` has to
be rebuilt.

Only set the macro where it is needed so that embedder string bumps
have minimal affects on ccache reuse.

Signed-off-by: Richard Lau <richard.lau@ibm.com>
---
 tools/v8_gypfiles/features.gypi |  3 ---
 tools/v8_gypfiles/v8.gyp        | 21 +++++++++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/tools/v8_gypfiles/features.gypi b/tools/v8_gypfiles/features.gypi
index 305c81eab34d..e782bc40642d 100644
--- a/tools/v8_gypfiles/features.gypi
+++ b/tools/v8_gypfiles/features.gypi
@@ -339,9 +339,6 @@
 
   'target_defaults': {
     'conditions': [
-      ['v8_embedder_string!=""', {
-        'defines': ['V8_EMBEDDER_STRING="<(v8_embedder_string)"',],
-      }],
       ['v8_enable_disassembler==1', {
         'defines': ['ENABLE_DISASSEMBLER',],
       }],
diff --git a/tools/v8_gypfiles/v8.gyp b/tools/v8_gypfiles/v8.gyp
index 71b6772bc345..e3ab38b543e2 100644
--- a/tools/v8_gypfiles/v8.gyp
+++ b/tools/v8_gypfiles/v8.gyp
@@ -558,6 +558,23 @@
         ],
       },
     },  # v8_version
+    {
+      'target_name': 'v8_version_string',
+      'type': 'static_library',
+      'toolsets': ['host', 'target'],
+      'dependencies': [
+        'v8_headers',
+        'v8_libbase',
+      ],
+      'sources': [
+        '<(V8_ROOT)/src/utils/version.cc',
+      ],
+      'conditions': [
+        ['v8_embedder_string!=""', {
+          'defines': ['V8_EMBEDDER_STRING="<(v8_embedder_string)"',],
+        }],
+      ],
+    },  # v8_version_string
     {
       'target_name': 'v8_config_headers',
       'type': 'none',
@@ -1106,6 +1123,7 @@
         'v8_libbase',
         'v8_shared_internal_headers',
         'v8_version',
+        'v8_version_string',
         'cppgc_base',
         'generate_bytecode_builtins_list',
         'run_torque',
@@ -1128,6 +1146,9 @@
 
         '<@(inspector_all_sources)',
       ],
+      'sources!': [
+        '<(V8_ROOT)/src/utils/version.cc', # now compiled in v8_version_string target
+      ],
       'conditions': [
         ['v8_use_perfetto==1', {
           'sources': [