diff --git a/library/dhm.c b/library/dhm.c
index 3daf0c2..e423657 100644
--- a/library/dhm.c
+++ b/library/dhm.c
@@ -51,7 +51,7 @@
     n = ((*p)[0] << 8) | (*p)[1];
     (*p) += 2;
 
-    if ((int) (end - *p) < n) {
+    if ((size_t) (end - *p) < (size_t) n) {
         return MBEDTLS_ERR_DHM_BAD_INPUT_DATA;
     }
 
@@ -257,7 +257,7 @@
     DHM_MPI_EXPORT(&ctx->G, n2);
     DHM_MPI_EXPORT(&ctx->GX, n3);
 
-    *olen = p - output;
+    *olen = (size_t) (p - output);
 
 cleanup:
     if (ret != 0 && ret > -128) {