diff --git a/configure.ac b/configure.ac
index 93bd47a..08786d8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -41,7 +41,7 @@ AC_TYPE_SIZE_T
 # Checks for library functions.
 dnl AC_FUNC_REALLOC
 AC_FUNC_STAT
-LDFLAGS='-lm'
+AC_CHECK_LIB([m],[sqrt])
 AC_CHECK_FUNCS([atexit floor getcwd memmove memset sqrt strdup strerror strrchr])