Re: compile warnings when including avltree-list and gcc-warnings is enabled

[Bruno Haible]

On 2014-09-16 Pádraig Brady wrote:
> I've adjusted and pushed your patch accordingly at:
> http://git.sv.gnu.org/gitweb/?p=gnulib.git;a=commitdiff;h=5549ef8

Now, on CentOS 8, with GCC 8.2.1 RedHat variant, I get this warning:

gl_avltree_list.c:67:1: warning: 'const' attribute on function returning 'void' 
[-Wattributes]

The warning is explained in [1]:
  "Note that a function that has pointer arguments and examines the data
   pointed to must not be declared const."

[1] https://gcc.gnu.org/onlinedocs/gcc-8.2.0/gcc/Common-Function-Attributes.html

If some GCC versions suggested to add 'const' on this function, this suggestion
was mistaken and should be silenced. In other words, don't use
-Werror=suggest-attribute=const with that version of GCC.


2019-09-29  Bruno Haible  <address@hidden>

        avltree-list: Fix compilation warning (introduced on 2014-09-16).
        * lib/gl_avltree_list.c (gl_avltree_list_check_invariants): Remove
        'const' attribute.

diff --git a/lib/gl_avltree_list.c b/lib/gl_avltree_list.c
index 655eeac..6d9a537 100644
--- a/lib/gl_avltree_list.c
+++ b/lib/gl_avltree_list.c
@@ -62,7 +62,7 @@ check_invariants (gl_list_node_t node, gl_list_node_t parent)
   return 1 + (left_height > right_height ? left_height : right_height);
 }
 
-void _GL_ATTRIBUTE_CONST
+void
 gl_avltree_list_check_invariants (gl_list_t list)
 {
   if (list->root != NULL)