diff --git a/artiq/firmware/Cargo.toml b/artiq/firmware/Cargo.toml
index 0f2007873..ec99844a5 100644
--- a/artiq/firmware/Cargo.toml
+++ b/artiq/firmware/Cargo.toml
@@ -1,2 +1,5 @@
 [workspace]
 members = ["bootloader", "runtime", "ksupport", "satman"]
+
+[profile.dev]
+debug = 1 # either 0 or 2 cause an LLVM ICE
diff --git a/conda/artiq-dev/meta.yaml b/conda/artiq-dev/meta.yaml
index d0aae5048..36be45c37 100644
--- a/conda/artiq-dev/meta.yaml
+++ b/conda/artiq-dev/meta.yaml
@@ -21,8 +21,7 @@ requirements:
     - binutils-or1k-linux >=2.27
     - llvm-or1k 4.0.1
     - llvmlite-artiq 0.20.0
-    - rustc 1.22.1 17
-    - rust-core-or1k 1.22.1 18
+    - rust-core-or1k 1.23.0 19
     - openocd 0.10.0+git1
     - lit
     - outputcheck