Removes -Wimplicit-fallthrough=5 from the gcc warnings

-Wimplicit-fallthrough=3 is added by -Wextra, which we already set.
Bumping the warning level only changes how fall-through comments are
parsed, with level 5 turning off fall-through comments entirely.
This is unnecessary and results in having to do extra work to squash
warnings when included external code uses fall-through.

This change also adds /* FALLTHROUGH */ comments where
H5_ATTR_FALLTHROUGH is used so compilers that don't use attributes
but do respect fall-through comments don't raise spurious warnings.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/H5SM.c b/src/H5SM.c
index 2e3fe04..52a5e8c 100644
--- a/src/H5SM.c
+++ b/src/H5SM.c
@@ -266,7 +266,7 @@ H5SM__type_to_flag(unsigned type_id, unsigned *type_flag)
     switch (type_id) {
         case H5O_FILL_ID:
             type_id = H5O_FILL_NEW_ID;
-            /* Fall through... */
+            /* FALLTHROUGH */
             H5_ATTR_FALLTHROUGH
 
         case H5O_SDSPACE_ID: