1 files changed, 4 insertions, 1 deletions
diff --git a/src/liballoc_jemalloc/lib.rs b/src/liballoc_jemalloc/lib.rs
index d02e9e4ba13..2c46e37ac32 100644
--- a/src/liballoc_jemalloc/lib.rs
+++ b/src/liballoc_jemalloc/lib.rs
@@ -38,7 +38,10 @@ use libc::{c_int, c_void, size_t};
                not(target_os = "android"),
                not(target_env = "musl")),
            link(name = "pthread"))]
-extern "C" {
+#[cfg(not(cargobuild))]
+extern {}
+
+extern {
     fn je_mallocx(size: size_t, flags: c_int) -> *mut c_void;
     fn je_rallocx(ptr: *mut c_void, size: size_t, flags: c_int) -> *mut c_void;
     fn je_xallocx(ptr: *mut c_void, size: size_t, extra: size_t, flags: c_int) -> size_t;