diff --git a/configure.in b/configure.in
index 52e07ced5..fc0bbd3e1 100644
--- a/configure.in
+++ b/configure.in
@@ -149,10 +149,13 @@ if test x$enable_libc = xyes; then
     if test x$ac_cv_func_strtod = xyes; then
         AC_DEFINE(HAVE_STRTOD)
     fi
-    AC_CHECK_FUNCS(malloc calloc realloc free getenv putenv unsetenv qsort abs bcopy memset memcpy memmove strlen strlcpy strlcat strdup _strrev _strupr _strlwr strchr strrchr strstr itoa _ltoa _uitoa _ultoa strtol strtoul _i64toa _ui64toa strtoll strtoull atoi atof strcmp strncmp _stricmp strcasecmp _strnicmp strncasecmp sscanf snprintf vsnprintf copysign cos cosf fabs floor log pow scalbn sin sinf sqrt iconv sigaction setjmp nanosleep)
+    AC_CHECK_FUNCS(malloc calloc realloc free getenv putenv unsetenv qsort abs bcopy memset memcpy memmove strlen strlcpy strlcat strdup _strrev _strupr _strlwr strchr strrchr strstr itoa _ltoa _uitoa _ultoa strtol strtoul _i64toa _ui64toa strtoll strtoull atoi atof strcmp strncmp _stricmp strcasecmp _strnicmp strncasecmp sscanf snprintf vsnprintf sigaction setjmp nanosleep)
 
-    AC_CHECK_LIB(m, pow, [EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lm"])
-    AC_CHECK_LIB(iconv, libiconv_open, [EXTRA_LDFLAGS="$EXTRA_LDFLAGS -liconv"])
+    AC_CHECK_LIB(m, pow, [LIBS="$LIBS -lm"; EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lm"])
+    AC_CHECK_FUNCS(copysign cos cosf fabs floor log pow scalbn sin sinf sqrt)
+
+    AC_CHECK_LIB(iconv, libiconv_open, [LIBS="$LIBS -liconv"; EXTRA_LDFLAGS="$EXTRA_LDFLAGS -liconv"])
+    AC_CHECK_FUNCS(iconv)
 fi
 
 if test x$have_inttypes != xyes; then