diff --git a/configure.ac b/configure.ac
index 4b42393..2394669 100644
--- a/configure.ac
+++ b/configure.ac
@@ -846,6 +846,8 @@ cat >> conftest.c <<EOF
         sparc64-linux-gnu
 # elif defined(__sparc__)
         sparc-linux-gnu
+# elif defined(__riscv) && defined(__riscv_xlen) && __riscv_xlen == 64
+       riscv64-linux-gnu
 # else
 #   error unknown platform triplet
 # endif