jemalloc: Fix jemalloc prefix for applications which expect ^malloc

pkgs/development/compilers/rustc/generic.nix

@@ -138,6 +138,10 @@ stdenv.mkDerivation {
     sed -i configure \
       -e '/probe_need CFG_CURLORWGET/d'
 
+    # Fix the use of jemalloc prefixes which our jemalloc doesn't have
+    [ -f src/liballoc_jemalloc/lib.rs ] && sed -i 's,je_,,g' src/liballoc_jemalloc/lib.rs
+    [ -f src/liballoc/heap.rs ] && sed -i 's,je_,,g' src/liballoc/heap.rs # Remove for 1.4.0+
+
     # Useful debugging parameter
     #export VERBOSE=1
   '';