[PATCH] configure: Use -Wimplicit-function-declaration if possible.

[Gijs Vermeulen]

This is enabled as an error by default starting with XCode 12.
Will prevent breaking the Staging CI.

Signed-off-by: Gijs Vermeulen <gijsvrm at gmail.com>
---
 configure.ac | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/configure.ac b/configure.ac
index 5c364bef0d9..101eafb478d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1044,6 +1044,7 @@ then
         WINE_TRY_CROSSCFLAGS([-Wdeclaration-after-statement])
         WINE_TRY_CROSSCFLAGS([-Wempty-body])
         WINE_TRY_CROSSCFLAGS([-Wignored-qualifiers])
+        WINE_TRY_CROSSCFLAGS([-Wimplicit-function-declaration])
         WINE_TRY_CROSSCFLAGS([-Winit-self])
         WINE_TRY_CROSSCFLAGS([-Wpacked-not-aligned],[EXTRACROSSCFLAGS="$EXTRACROSSCFLAGS -Wno-packed-not-aligned"])
         WINE_TRY_CROSSCFLAGS([-Wpragma-pack],[EXTRACROSSCFLAGS="$EXTRACROSSCFLAGS -Wno-pragma-pack"])
@@ -2016,6 +2017,7 @@ then
   WINE_TRY_CFLAGS([-Wdeclaration-after-statement])
   WINE_TRY_CFLAGS([-Wempty-body])
   WINE_TRY_CFLAGS([-Wignored-qualifiers])
+  WINE_TRY_CFLAGS([-Wimplicit-function-declaration])
   WINE_TRY_CFLAGS([-Winit-self])
   WINE_TRY_CFLAGS([-Wpacked-not-aligned],[EXTRACFLAGS="$EXTRACFLAGS -Wno-packed-not-aligned"])
   WINE_TRY_CFLAGS([-Wpragma-pack],[EXTRACFLAGS="$EXTRACFLAGS -Wno-pragma-pack"])
-- 
2.31.1