Document that get_direct_buffer is not fully aligned

README.md

@@ -941,9 +941,10 @@ Namespaces can be long so we optionally use a macro to manage this.
         }
 
         /*
-         * If we retrieved the buffer using `flatcc_builder_finalize_aligned_buffer` or
-         * `flatcc_builder_get_direct_buffer` the struct should also
-         * be aligned without subtracting the buffer.
+         * If we retrieved the buffer using `flatcc_builder_finalize_aligned_buffer`
+         * the buffer should be correctly aligned. If the simpler
+         * `flatcc_builder_get_direct_buffer` is used, alignment above 4 bytes is
+         * not guaranteed.
          */
         if (vec & 15) {
             printf("warning: buffer not aligned in memory\n");
@@ -1024,10 +1025,13 @@ to provide a custom emitter and for example emit pages over the network
 as soon as they complete rather than merging all pages into a single
 buffer using `flatcc_builder_finalize_buffer`, or the simplistic
 `flatcc_builder_get_direct_buffer` which returns null if the buffer is
-too large. See also documentation comments in [flatcc_builder.h] and
-[flatcc_emitter.h]. See also `flatc_builder_finalize_aligned_buffer` in
+too large. Note that the direct buffer variant does not guarantee full
+alignment above 4 bytes in the current memory location but can be copied
+to an aligned location. See also documentation comments in
+[flatcc_builder.h] and [flatcc_emitter.h].
+See also `flatc_builder_finalize_aligned_buffer` in
 `builder.h` and the [Builder Interface Reference] when malloc aligned
-buffers are insufficent.
+or direct buffers are insufficent.
 
 
     #include "monster_test_builder.h"

include/flatcc/flatcc_builder.h

@@ -1793,7 +1793,10 @@ char *flatcc_builder_string_edit(flatcc_builder_t *B);
 /*
  * Only for use with the default emitter.
  *
- * Fast acces to small buffers from default emitter.
+ * Fast acces to small buffers from default emitter where alignment
+ * above 4 bytes (`sizeof(flatbuffers_uoffset_t)`) is not important.
+ * The buffer is correctly alignmed internally but the current start
+ * of the buffer might not be before being copied.
  *
  * Only valid for default emitters before `flatcc_builder_clear`. The
  * return buffer is not valid after a call to `flatcc_builder_reset` or