Fix some of the problems reported by cppcheck

Thanks to Christian for running the static code analysis tool against
subsurface...

There were some false positives, a few style issues that I'll ignore for
now, and two actual potential bugs.

First: Don't check unsigned variables for < 0

This has been around for a while and we are lucky that while technically a
bug it still works as expected. Passing a negative idx simply turns it
into a very large unsigned integer which then fails the > dive_table.nr
test. So it still gets a NULL returned. A bug? Yes. Critical? No.

Mismatched allocation and free

This is an actual bug that potentially could cause issues. We allocate
memory with malloc and free it with g_free. Not good.

Reported-by: Cristian Ionescu-Idbohrn <cristian.ionescu-idbohrn@axis.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/gtk-gui.c b/gtk-gui.c
index d797b8d56..167517ebe 100644
--- a/gtk-gui.c
+++ b/gtk-gui.c
@@ -226,7 +226,7 @@ static gboolean ask_save_changes()
 			"You have unsaved changes to file: %s \nWould you like to save those before closing the datafile?",
 			existing_filename);
 		label = gtk_label_new (label_text);
-		g_free(label_text);
+		free(label_text);
 	}
 	gtk_container_add (GTK_CONTAINER (content), label);
 	gtk_widget_show_all (dialog);