meson: Fix MSVC build with GST_DISABLE_GST_DEBUG

MSVC does not understand Wno-unused

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5585>

subprojects/gst-editing-services/meson.build

@@ -57,8 +57,6 @@ if cc.get_id() == 'msvc'
 
       # Enable some warnings on MSVC to match GCC/Clang behaviour
       '/w14062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
-      '/w14101', # 'identifier' : unreferenced local variable
-      '/w14189', # 'identifier' : local variable is initialized but not referenced
   ]
   add_project_arguments(msvc_args, language: 'c')
 endif
@@ -233,8 +231,26 @@ else
   gst_debug_disabled = cc.has_header_symbol('gst/gstconfig.h', 'GST_DISABLE_GST_DEBUG', dependencies: gst_dep)
 endif
 
-if gst_debug_disabled and cc.has_argument('-Wno-unused')
-  add_project_arguments('-Wno-unused', language: 'c')
+if gst_debug_disabled
+  message('GStreamer debug system is disabled')
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  elif cc.has_argument('-Wno-unused')
+    add_project_arguments(['-Wno-unused'], language: 'c')
+  endif
+else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  endif
+  message('GStreamer debug system is enabled')
 endif
 
 warning_flags = [

subprojects/gst-libav/meson.build

@@ -133,8 +133,6 @@ if cc.get_id() == 'msvc'
       '/we4053', # one void operand for '?:'
       '/we4062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
       '/we4098', # 'function' : void function returning a value
-      '/we4101', # 'identifier' : unreferenced local variable
-      '/we4189', # 'identifier' : local variable is initialized but not referenced
     ])
   endif
   add_project_arguments(msvc_args, language: ['c', 'cpp'])
@@ -161,28 +159,36 @@ if cc.has_argument('-fno-strict-aliasing')
   add_project_arguments('-fno-strict-aliasing', language: 'c')
 endif
 
+# Disable compiler warnings for unused variables and args if gst debug system is disabled
 if gst_dep.type_name() == 'internal'
   gst_proj = subproject('gstreamer')
-
-    if not gst_proj.get_variable('gst_debug')
-        message('GStreamer debug system is disabled')
-        add_project_arguments('-Wno-unused', language: 'c')
-    else
-        message('GStreamer debug system is enabled')
-    endif
+  gst_debug_disabled = not gst_proj.get_variable('gst_debug')
 else
   # We can't check that in the case of subprojects as we won't
   # be able to build against an internal dependency (which is not built yet)
-    if not cc.compiles('''
-#include <gst/gstconfig.h>
-#ifdef GST_DISABLE_GST_DEBUG
-#error "debugging disabled, make compiler fail"
-#endif''' , dependencies: gst_dep)
+  gst_debug_disabled = cc.has_header_symbol('gst/gstconfig.h', 'GST_DISABLE_GST_DEBUG', dependencies: gst_dep)
+endif
+
+if gst_debug_disabled
   message('GStreamer debug system is disabled')
-        add_project_arguments('-Wno-unused', language: 'c')
-    else
-        message('GStreamer debug system is enabled')
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  elif cc.has_argument('-Wno-unused')
+    add_project_arguments(['-Wno-unused'], language: 'c')
   endif
+else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  endif
+  message('GStreamer debug system is enabled')
 endif
 
 warning_flags = [

subprojects/gst-plugins-bad/meson.build

@@ -83,8 +83,6 @@ if cc.get_id() == 'msvc'
       '/we4053', # one void operand for '?:'
       '/we4062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
       '/we4098', # 'function' : void function returning a value
-      '/we4101', # 'identifier' : unreferenced local variable
-      '/we4189', # 'identifier' : local variable is initialized but not referenced
     ])
   endif
   add_project_arguments(msvc_args, language: ['c', 'cpp'])
@@ -489,13 +487,28 @@ endif
 
 if gst_debug_disabled
   message('GStreamer debug system is disabled')
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: ['c', 'cpp'])
+  else
     if cc.has_argument('-Wno-unused')
       add_project_arguments('-Wno-unused', language: 'c')
     endif
     if cxx.has_argument ('-Wno-unused')
       add_project_arguments('-Wno-unused', language: 'cpp')
     endif
+  endif
 else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: ['c', 'cpp'])
+  endif
   message('GStreamer debug system is enabled')
 endif
 

subprojects/gst-plugins-base/meson.build

@@ -79,8 +79,6 @@ if cc.get_id() == 'msvc'
       '/we4053', # one void operand for '?:'
       '/we4062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
       '/we4098', # 'function' : void function returning a value
-      '/we4101', # 'identifier' : unreferenced local variable
-      '/we4189', # 'identifier' : local variable is initialized but not referenced
     ])
   endif
   add_project_arguments(msvc_args, language: ['c', 'cpp'])
@@ -410,28 +408,36 @@ int32x4_t testfunc(int16_t *a, int16_t *b) {
   endif
 endif
 
+# Disable compiler warnings for unused variables and args if gst debug system is disabled
 if gst_dep.type_name() == 'internal'
   gst_proj = subproject('gstreamer')
-
-    if not gst_proj.get_variable('gst_debug')
-        message('GStreamer debug system is disabled')
-        add_project_arguments('-Wno-unused', language: 'c')
-    else
-        message('GStreamer debug system is enabled')
-    endif
+  gst_debug_disabled = not gst_proj.get_variable('gst_debug')
 else
   # We can't check that in the case of subprojects as we won't
   # be able to build against an internal dependency (which is not built yet)
-    if not cc.compiles('''
-#include <gst/gstconfig.h>
-#ifdef GST_DISABLE_GST_DEBUG
-#error "debugging disabled, make compiler fail"
-#endif''' , dependencies: gst_dep)
+  gst_debug_disabled = cc.has_header_symbol('gst/gstconfig.h', 'GST_DISABLE_GST_DEBUG', dependencies: gst_dep)
+endif
+
+if gst_debug_disabled
   message('GStreamer debug system is disabled')
-        add_project_arguments('-Wno-unused', language: 'c')
-    else
-        message('GStreamer debug system is enabled')
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  elif cc.has_argument('-Wno-unused')
+    add_project_arguments(['-Wno-unused'], language: 'c')
   endif
+else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  endif
+  message('GStreamer debug system is enabled')
 endif
 
 if cc.has_member('struct tcp_info', '__tcpi_reordering', prefix: '#include <netinet/tcp.h>')

subprojects/gst-plugins-good/meson.build

@@ -68,8 +68,6 @@ if cc.get_id() == 'msvc'
       '/we4053', # one void operand for '?:'
       '/we4062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
       '/we4098', # 'function' : void function returning a value
-      '/we4101', # 'identifier' : unreferenced local variable
-      '/we4189', # 'identifier' : local variable is initialized but not referenced
     ])
   endif
   if have_cxx
@@ -457,13 +455,28 @@ endif
 
 if gst_debug_disabled
   message('GStreamer debug system is disabled')
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: ['c', 'cpp'])
+  else
     if cc.has_argument('-Wno-unused')
       add_project_arguments('-Wno-unused', language: 'c')
     endif
     if have_cxx and cxx.has_argument ('-Wno-unused')
       add_project_arguments('-Wno-unused', language: 'cpp')
     endif
+  endif
 else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: ['c', 'cpp'])
+  endif
   message('GStreamer debug system is enabled')
 endif
 

subprojects/gst-plugins-ugly/meson.build

@@ -66,8 +66,6 @@ if cc.get_id() == 'msvc'
       '/we4053', # one void operand for '?:'
       '/we4062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
       '/we4098', # 'function' : void function returning a value
-      '/we4101', # 'identifier' : unreferenced local variable
-      '/we4189', # 'identifier' : local variable is initialized but not referenced
     ])
   endif
   if have_cxx
@@ -220,13 +218,28 @@ endif
 
 if gst_debug_disabled
   message('GStreamer debug system is disabled')
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: ['c', 'cpp'])
+  else
     if cc.has_argument('-Wno-unused')
       add_project_arguments('-Wno-unused', language: 'c')
     endif
     if have_cxx and cxx.has_argument ('-Wno-unused')
       add_project_arguments('-Wno-unused', language: 'cpp')
     endif
+  endif
 else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: ['c', 'cpp'])
+  endif
   message('GStreamer debug system is enabled')
 endif
 

subprojects/gstreamer/meson.build

@@ -76,8 +76,6 @@ if cc.get_id() == 'msvc'
       '/we4053', # one void operand for '?:'
       '/we4062', # enumerator 'identifier' in switch of enum 'enumeration' is not handled
       '/we4098', # 'function' : void function returning a value
-      '/we4101', # 'identifier' : unreferenced local variable
-      '/we4189', # 'identifier' : local variable is initialized but not referenced
     ])
   endif
   add_project_arguments(msvc_args, language: 'c')
@@ -488,7 +486,23 @@ endif
 
 gst_debug = get_option('gst_debug')
 if not gst_debug
+  if cc.get_argument_syntax() == 'msvc'
+    msvc_args = cc.get_supported_arguments([
+      '/wd4101', # 'identifier' : unreferenced local variable
+      '/wd4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  elif cc.has_argument('-Wno-unused')
     add_project_arguments(['-Wno-unused'], language: 'c')
+  endif
+else
+  if cc.get_argument_syntax() == 'msvc' and gst_version_is_dev
+    msvc_args = cc.get_supported_arguments([
+      '/we4101', # 'identifier' : unreferenced local variable
+      '/we4189', # 'identifier' : local variable is initialized but not referenced
+    ])
+    add_project_arguments(msvc_args, language: 'c')
+  endif
 endif
 
 warning_flags = [