diff --git a/CMakeLists.txt b/CMakeLists.txt
index 72d8c54e9..ceab5a8ef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,13 +61,13 @@ set (CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
 # set version of the project
 set(LIBYANG_MAJOR_VERSION 6)
 set(LIBYANG_MINOR_VERSION 4)
-set(LIBYANG_MICRO_VERSION 3)
+set(LIBYANG_MICRO_VERSION 4)
 set(LIBYANG_VERSION ${LIBYANG_MAJOR_VERSION}.${LIBYANG_MINOR_VERSION}.${LIBYANG_MICRO_VERSION})
 
 # set version of the library
 set(LIBYANG_MAJOR_SOVERSION 5)
 set(LIBYANG_MINOR_SOVERSION 11)
-set(LIBYANG_MICRO_SOVERSION 1)
+set(LIBYANG_MICRO_SOVERSION 2)
 set(LIBYANG_SOVERSION_FULL ${LIBYANG_MAJOR_SOVERSION}.${LIBYANG_MINOR_SOVERSION}.${LIBYANG_MICRO_SOVERSION})
 set(LIBYANG_SOVERSION ${LIBYANG_MAJOR_SOVERSION})
 
diff --git a/src/diff.c b/src/diff.c
index e22f7c949..0ece51d50 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -824,7 +824,7 @@ lyd_diff_userord_attrs(const struct lyd_node *first, const struct lyd_node *seco
      */
     if (*op == LYD_DIFF_OP_CREATE) {
         /* insert the instance */
-        LYA_PREALLOC(userord_item->inst, 1, LOGMEM(schema->module->ctx); rc = LY_EMEM; goto cleanup);
+        LYA_PREALLOC(userord_item->inst, LYA_COUNT(userord_item->inst) + 1, LOGMEM(schema->module->ctx); rc = LY_EMEM; goto cleanup);
         if (second_pos < LYA_COUNT(userord_item->inst)) {
             memmove(userord_item->inst + second_pos + 1, userord_item->inst + second_pos,
                     (LYA_COUNT(userord_item->inst) - second_pos) * sizeof *userord_item->inst);
diff --git a/src/ly_array.h b/src/ly_array.h
index 07681877c..081f8e108 100644
--- a/src/ly_array.h
+++ b/src/ly_array.h
@@ -88,7 +88,7 @@ extern "C" {
  * Does not set the size information, it is supposed to be incremented via ::LYA_INCREMENT
  * when the items are filled.
  *
- * Any new memory is zeroed.
+ * Any new memory is zeroed. The array is never shrunk below its current count.
  *
  * @param[in,out] ARRAY Sized array to manipulate.
  * @param[in] COUNT New count (size) of the items in the array.
@@ -96,18 +96,20 @@ extern "C" {
  */
 #define LYA_PREALLOC(ARRAY, COUNT, EACTION) \
     { \
-        LYA_COUNT_T orig_count = LYA_COUNT(ARRAY); \
-        void *mem = realloc((ARRAY) ? (LYA_COUNT_T *)(ARRAY) - 1 : NULL, \
-                sizeof(LYA_COUNT_T) + (orig_count + COUNT) * sizeof *(ARRAY)); \
-        if (!mem) { \
-            EACTION; \
+        LYA_COUNT_T lya_prealloc_orig = LYA_COUNT(ARRAY); \
+        LYA_COUNT_T lya_prealloc_count = (COUNT); \
+        if (lya_prealloc_count < lya_prealloc_orig) { \
+            lya_prealloc_count = lya_prealloc_orig; \
         } \
-        void *new_array = (LYA_COUNT_T *)mem + 1; \
-        memcpy(&(ARRAY), &new_array, sizeof(ARRAY)); \
-        LYA_COUNT_(ARRAY) = orig_count; \
-        if ((COUNT) > orig_count) { \
-            memset((ARRAY) + orig_count, 0, ((COUNT) - orig_count) * sizeof *(ARRAY)); \
+        void *lya_prealloc_mem = realloc((ARRAY) ? (LYA_COUNT_T *)(ARRAY) - 1 : NULL, \
+                sizeof(LYA_COUNT_T) + lya_prealloc_count * sizeof *(ARRAY)); \
+        if (!lya_prealloc_mem) { \
+            EACTION; \
         } \
+        void *lya_prealloc_array = (LYA_COUNT_T *)lya_prealloc_mem + 1; \
+        memcpy(&(ARRAY), &lya_prealloc_array, sizeof(ARRAY)); \
+        LYA_COUNT_(ARRAY) = lya_prealloc_orig; \
+        memset((ARRAY) + lya_prealloc_orig, 0, (lya_prealloc_count - lya_prealloc_orig) * sizeof *(ARRAY)); \
     }
 
 /**
diff --git a/src/path.c b/src/path.c
index 5cccf05a1..d5e59dce7 100644
--- a/src/path.c
+++ b/src/path.c
@@ -974,7 +974,7 @@ ly_path_append(const struct ly_ctx *ctx, const struct ly_path *src, struct ly_pa
         return LY_SUCCESS;
     }
 
-    LYA_PREALLOC(*dst, LYA_COUNT(src), LOGMEM(ctx); return LY_EMEM);
+    LYA_PREALLOC(*dst, LYA_COUNT(*dst) + LYA_COUNT(src), LOGMEM(ctx); return LY_EMEM);
     LYA_FOR(src, u) {
         LYA_ADD_ITEM(*dst, p, LOGMEM(ctx); rc = LY_EMEM; goto cleanup);
         p->node = src[u].node;
diff --git a/src/schema_compile.h b/src/schema_compile.h
index 9337760b9..5b3adbde7 100644
--- a/src/schema_compile.h
+++ b/src/schema_compile.h
@@ -186,7 +186,7 @@ struct lysc_unres_dflt {
     if (ORIG_ARRAY) { \
         LYA_COUNT_T __u, __new_start; \
         __new_start = LYA_COUNT(NEW_ARRAY); \
-        LYA_PREALLOC(NEW_ARRAY, LYA_COUNT(ORIG_ARRAY), LOGMEM(CTX); return LY_EMEM); \
+        LYA_PREALLOC(NEW_ARRAY, __new_start + LYA_COUNT(ORIG_ARRAY), LOGMEM(CTX); return LY_EMEM); \
         LYA_FOR(ORIG_ARRAY, __u) { \
             LYA_INCREMENT(NEW_ARRAY); \
             LY_CHECK_RET(DUP_FUNC(CTX, PMOD, PARENT, PARENT_STMT, &(ORIG_ARRAY)[__u], &(NEW_ARRAY)[__new_start + __u])); \
diff --git a/src/schema_compile_node.c b/src/schema_compile_node.c
index 6a87e54aa..2ad151b97 100644
--- a/src/schema_compile_node.c
+++ b/src/schema_compile_node.c
@@ -1450,8 +1450,8 @@ lys_compile_type_union(struct lysc_ctx *ctx, struct lysp_type *ptypes, struct ly
         if (utypes[u + additional]->basetype == LY_TYPE_UNION) {
             /* add space for additional types from the union subtype */
             un_aux = (struct lysc_type_union *)utypes[u + additional];
-            LYA_PREALLOC(utypes, LYA_COUNT(ptypes) + additional + LYA_COUNT(un_aux->types) - LYA_COUNT(utypes),
-                    LOGMEM(ctx->ctx); rc = LY_EMEM; goto cleanup);
+            LYA_PREALLOC(utypes, LYA_COUNT(ptypes) + additional + LYA_COUNT(un_aux->types), LOGMEM(ctx->ctx);
+                    rc = LY_EMEM; goto cleanup);
 
             /* copy subtypes of the subtype union */
             for (v = 0; v < LYA_COUNT(un_aux->types); ++v) {