diff --git a/src/bootstrap/native.rs b/src/bootstrap/native.rs
index d9dc9df823a56..2cbae083fc464 100644
--- a/src/bootstrap/native.rs
+++ b/src/bootstrap/native.rs
@@ -417,6 +417,7 @@ impl Step for Openssl {
             "powerpc64-unknown-linux-gnu" => "linux-ppc64",
             "powerpc64le-unknown-linux-gnu" => "linux-ppc64le",
             "s390x-unknown-linux-gnu" => "linux64-s390x",
+            "sparc64-unknown-netbsd" => "BSD-sparc64",
             "x86_64-apple-darwin" => "darwin64-x86_64-cc",
             "x86_64-linux-android" => "linux-x86_64",
             "x86_64-unknown-freebsd" => "BSD-x86_64",
@@ -436,6 +437,15 @@ impl Step for Openssl {
             configure.arg("-mandroid");
             configure.arg("-fomit-frame-pointer");
         }
+        if target == "sparc64-unknown-netbsd" {
+            // Need -m64 to get assembly generated correctly for sparc64.
+            configure.arg("-m64");
+            if build.build.contains("netbsd") {
+                // Disable sparc64 asm on NetBSD builders, it uses
+                // m4(1)'s -B flag, which NetBSD m4 does not support.
+                configure.arg("no-asm");
+            }
+        }
         // Make PIE binaries
         // Non-PIE linker support was removed in Lollipop
         // https://source.android.com/security/enhancements/enhancements50