qt,cpp: Consistently use nullptr and override

* lang/cpp/src/Makefile.am, lang/qt/src/Makefile.am (AM_CPPFLAGS):
Add suggest-override and zero-as-null-pointer-constant warnings.

* lang/cpp/src/*, lang/qt/src/*: Consistenly use nullptr and override.

--
This was especially important for the headers so that downstream
users of GpgME++ or QGpgME do not get flooded by warnings if
they have these warnings enabled.

It also improves compiler errors/warnings in case of accidental
mistakes.

1 files changed, 2 insertions, 2 deletions

diff --git a/lang/qt/src/cryptoconfig.h b/lang/qt/src/cryptoconfig.h
index d545e597..d7aae9d7 100644
--- a/lang/qt/src/cryptoconfig.h
+++ b/lang/qt/src/cryptoconfig.h
@@ -382,8 +382,8 @@ public:
     CryptoConfigEntry *entry(const QString &componentName, const QString &groupName, const QString &entryName) const
     {
         const QGpgME::CryptoConfigComponent *comp = component(componentName);
-        const QGpgME::CryptoConfigGroup *group = comp ? comp->group(groupName) : 0;
-        return group ? group->entry(entryName) : 0;
+        const QGpgME::CryptoConfigGroup *group = comp ? comp->group(groupName) : nullptr;
+        return group ? group->entry(entryName) : nullptr;
     }
 
     /**