meson.build: Skip GCC/Clang-only flags on MSVC

get_supported_arguments() doesn't reliably filter flags on MSVC (e.g.
-fstack-protector-strong passes the probe but emits D9002 at compile
time). Guard the extra_flags block with a compiler id check.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: andy5995

meson.build

@@ -8,17 +8,18 @@ project(
 
 cc = meson.get_compiler('c')
 
-extra_flags = [
-  '-fno-common',
-  '-fstack-protector-strong',
-  '-Wformat-security',
-  '-Wshadow',
-  '-Wstrict-overflow=5',
-  '-Werror=odr',
-  '-Werror=strict-aliasing',
-]
-
-add_project_arguments(cc.get_supported_arguments(extra_flags), language: 'c')
+if cc.get_id() != 'msvc'
+  extra_flags = [
+    '-fno-common',
+    '-fstack-protector-strong',
+    '-Wformat-security',
+    '-Wshadow',
+    '-Wstrict-overflow=5',
+    '-Werror=odr',
+    '-Werror=strict-aliasing',
+  ]
+  add_project_arguments(cc.get_supported_arguments(extra_flags), language: 'c')
+endif
 
 # Parse version components
 version_components = meson.project_version().split('.')

subprojects/pcg/meson.build

@@ -8,17 +8,18 @@ project(
 
 cc = meson.get_compiler('c')
 
-extra_flags = [
-    '-fno-common',
-    '-fstack-protector-strong',
-    '-Wformat-security',
-    '-Wshadow',
-    '-Wstrict-overflow=5',
-    '-Werror=odr',
-    '-Werror=strict-aliasing',
-]
-
-add_project_arguments(cc.get_supported_arguments(extra_flags), language: 'c')
+if cc.get_id() != 'msvc'
+  extra_flags = [
+      '-fno-common',
+      '-fstack-protector-strong',
+      '-Wformat-security',
+      '-Wshadow',
+      '-Wstrict-overflow=5',
+      '-Werror=odr',
+      '-Werror=strict-aliasing',
+  ]
+  add_project_arguments(cc.get_supported_arguments(extra_flags), language: 'c')
+endif
 
 _pcg = static_library('pcg', 'pcg_basic.c')