diff --git a/compat/regex/regex.c b/compat/regex/regex.c
index f3e03a9eab..e6f4a5d177 100644
--- a/compat/regex/regex.c
+++ b/compat/regex/regex.c
@@ -60,6 +60,7 @@
    #undefs RE_DUP_MAX and sets it to the right value.  */
 #include <limits.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 #ifdef GAWK
 #undef alloca
diff --git a/compat/regex/regex_internal.h b/compat/regex/regex_internal.h
index 3ee8aae59d..0bad8b841e 100644
--- a/compat/regex/regex_internal.h
+++ b/compat/regex/regex_internal.h
@@ -23,7 +23,6 @@
 #include <assert.h>
 #include <ctype.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
 
 #if defined HAVE_LANGINFO_H || defined HAVE_LANGINFO_CODESET || defined _LIBC