diff --git a/portage/env/nolto.conf b/portage/env/nolto.conf
index 3495359..e55fb28 100644
--- a/portage/env/nolto.conf
+++ b/portage/env/nolto.conf
@@ -14,7 +14,7 @@ LD_SEC="-Wl,-pie -Wl,--strip-all -Wl,-z,defs -Wl,-z,now -Wl,-z,relro"
 ## Compiler flags.
 CFLAGS="-march=znver3 -O2 -pipe -U__gnu_linux__ ${C_SEC}"
 CXXFLAGS="-march=znver3 -O2 -pipe ${C_SEC}"
-RUSTFLAGS="-C target-cpu=znver3 -C opt-level=2 -C debuginfo=0"
+RUSTFLAGS="-Ctarget-cpu=znver3 -Copt-level=2 -Cdebuginfo=0"
 
 ## Linker flags.
 LDFLAGS="-fuse-ld=lld -rtlib=compiler-rt -unwindlib=libunwind ${LD_SEC}"