diff --git a/include/crm/common/group_internal.h b/include/crm/common/group_internal.h
index 220b007a78..ceee6d4527 100644
--- a/include/crm/common/group_internal.h
+++ b/include/crm/common/group_internal.h
@@ -1,48 +1,55 @@
 /*
- * Copyright 2004-2024 the Pacemaker project contributors
+ * Copyright 2004-2025 the Pacemaker project contributors
  *
  * The version control history for this file may have further details.
  *
  * This source code is licensed under the GNU Lesser General Public License
  * version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
  */
 
 #ifndef PCMK__CRM_COMMON_GROUP_INTERNAL__H
 #define PCMK__CRM_COMMON_GROUP_INTERNAL__H
 
 #include <stdio.h>                          // NULL
 #include <stdbool.h>                        // bool
+#include <stdint.h>                         // UINT32_C
 #include <crm/common/scheduler_types.h>     // pcmk_resource_t
 #include <crm/common/resources_internal.h>  // pcmk__rsc_variant_group etc.
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-// Group resource flags (used in variant data)
+/*!
+ * \internal
+ * \brief Group resource flags (used in variant data)
+ */
 enum pcmk__group_flags {
-    pcmk__group_ordered     = (1 << 0), // Members start sequentially
-    pcmk__group_colocated   = (1 << 1), // Members must be on same node
+    //! Members start sequentially
+    pcmk__group_ordered     = (UINT32_C(1) << 0),
+
+    //! Members must be on same node
+    pcmk__group_colocated   = (UINT32_C(1) << 1),
 };
 
 /*!
  * \internal
  * \brief Check whether a resource is a group resource
  *
  * \param[in] rsc  Resource to check
  *
  * \return true if \p rsc is a group, otherwise false
  *
  * \note This does not return true if \p rsc is a clone of a group.
  */
 static inline bool
 pcmk__is_group(const pcmk_resource_t *rsc)
 {
     return (rsc != NULL) && (rsc->priv->variant == pcmk__rsc_variant_group);
 }
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif // PCMK__CRM_COMMON_GROUP_INTERNAL__H