[PATCH v4 4/4] meson: Warn when TCI is selected but TCG backend is available

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Some new users get confused with 'TCG' and 'TCI', and enable TCI
support expecting to enable TCG.

Emit a warning when native TCG backend is available on the
host architecture, mentioning this is a suboptimal configuration.

Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Suggested-by: Daniel Berrangé <berrange@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 meson.build | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/meson.build b/meson.build
index 16b2560e7e7..f675c54e636 100644
--- a/meson.build
+++ b/meson.build
@@ -228,6 +228,13 @@
     else
       error('Unsupported CPU @0@, try --enable-tcg-interpreter'.format(cpu))
     endif
+  elif get_option('tcg_interpreter')
+    warning('Use of the TCG interpretor is not recommended on this host')
+    warning('architecture. There is a native TCG execution backend available')
+    warning('which provides substantially better performance and reliability.')
+    warning('It is strongly recommended to remove the --enable-tcg-interpreter')
+    warning('configuration option on this architecture to use the native')
+    warning('backend.')
   endif
   if get_option('tcg_interpreter')
     tcg_arch = 'tci'
-- 
2.26.2