build: add --error-on-warn configure flag

This commit adds a configuration time flag named error-on-warn:
$ ./configure --help | grep -A1 error-on-warn
  --error-on-warn       Turn compiler warnings into errors for node core
                        sources.

The motivation for this is that CI jobs can use this flag to turn
warnings into errors.

PR-URL: https://github.com/nodejs/node/pull/32685
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Matheus Marchini <mat@mmarchini.me>

1 files changed, 6 insertions, 0 deletions

diff --git a/node.gyp b/node.gyp
index 2f0f0f152b..3dadad15c9 100644
--- a/node.gyp
+++ b/node.gyp
@@ -376,6 +376,9 @@
       'msvs_disabled_warnings!': [4244],
 
       'conditions': [
+        [ 'error_on_warn=="true"', {
+          'cflags': ['-Werror'],
+        }],
         [ 'node_intermediate_lib_type=="static_library" and '
             'node_shared=="true" and OS=="aix"', {
           # For AIX, shared lib is linked by static lib and .exp. In the
@@ -750,6 +753,9 @@
       'msvs_disabled_warnings!': [4244],
 
       'conditions': [
+        [ 'error_on_warn=="true"', {
+          'cflags': ['-Werror'],
+        }],
         [ 'node_builtin_modules_path!=""', {
           'defines': [ 'NODE_BUILTIN_MODULES_PATH="<(node_builtin_modules_path)"' ]
         }],