3 files changed, 34 insertions, 0 deletions
diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
index ff673665d86..dfbc22970f8 100644
--- a/src/bin/psql/common.c
+++ b/src/bin/psql/common.c
@@ -786,6 +786,13 @@ StoreQueryTuple(const PGresult *result)
 			/* concatenate prefix and column name */
 			varname = psprintf("%s%s", pset.gset_prefix, colname);
 
+			if (VariableHasHook(pset.vars, varname))
+			{
+				pg_log_warning("attempt to \\gset into specially treated variable \"%s\" ignored",
+							   varname);
+				continue;
+			}
+
 			if (!PQgetisnull(result, 0, i))
 				value = PQgetvalue(result, 0, i);
 			else
diff --git a/src/bin/psql/variables.c b/src/bin/psql/variables.c
index 52aa5e5f164..84349fc753f 100644
--- a/src/bin/psql/variables.c
+++ b/src/bin/psql/variables.c
@@ -361,6 +361,32 @@ SetVariableHooks(VariableSpace space, const char *name,
 }
 
 /*
+ * Return true iff the named variable has substitute and/or assign hook
+ * functions.
+ */
+bool
+VariableHasHook(VariableSpace space, const char *name)
+{
+	struct _variable *current;
+
+	Assert(space);
+	Assert(name);
+
+	for (current = space->next; current; current = current->next)
+	{
+		int			cmp = strcmp(current->name, name);
+
+		if (cmp == 0)
+			return (current->substitute_hook != NULL ||
+					current->assign_hook != NULL);
+		if (cmp > 0)
+			break;				/* it's not there */
+	}
+
+	return false;
+}
+
+/*
  * Convenience function to set a variable's value to "on".
  */
 bool
diff --git a/src/bin/psql/variables.h b/src/bin/psql/variables.h
index ab5e51f20b5..b932472021a 100644
--- a/src/bin/psql/variables.h
+++ b/src/bin/psql/variables.h
@@ -90,6 +90,7 @@ bool		DeleteVariable(VariableSpace space, const char *name);
 void		SetVariableHooks(VariableSpace space, const char *name,
 							 VariableSubstituteHook shook,
 							 VariableAssignHook ahook);
+bool		VariableHasHook(VariableSpace space, const char *name);
 
 void		PsqlVarEnumError(const char *name, const char *value, const char *suggestions);