diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 78f7114..0262f5f 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -34,9 +34,14 @@ jobs:
             cross_cmake_args: >-
               -DCMAKE_SYSTEM_NAME=Linux
               -DCMAKE_SYSTEM_PROCESSOR=riscv64
+              -DCMAKE_C_COMPILER=riscv64-linux-gnu-gcc
+              -DCMAKE_CXX_COMPILER=riscv64-linux-gnu-g++
               -DWASI_SDK_LLDB=OFF
             env:
               WASI_SDK_CI_SKIP_SYSROOT: 1
+              WASI_SDK_CI_TOOLCHAIN_LLVM_CMAKE_ARGS: >-
+                -DCMAKE_SYSTEM_NAME=Linux
+                -DCMAKE_SYSTEM_PROCESSOR=riscv64
 
           - artifact: arm64-macos
             os: macos-14
diff --git a/ci/docker/Dockerfile.riscv64-linux b/ci/docker/Dockerfile.riscv64-linux
index 6012568..f4456ec 100644
--- a/ci/docker/Dockerfile.riscv64-linux
+++ b/ci/docker/Dockerfile.riscv64-linux
@@ -16,13 +16,11 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   ccache \
   && rm -rf /var/lib/apt/lists/*
 
-# Set the cross-compiler as the default so that cmake picks it up via CC/CXX
-# and sets CMAKE_CROSSCOMPILING=TRUE, which causes LLVM to build a native
-# tablegen before cross-compiling the rest of the toolchain.
-ENV CC=riscv64-linux-gnu-gcc
-ENV CXX=riscv64-linux-gnu-g++
-
 # Cargo needs an explicit linker when cross-compiling for riscv64.
+# The C/C++ cross-compiler is passed via CMAKE_C/CXX_COMPILER cmake flags
+# rather than CC/CXX env vars so that LLVM's native tblgen sub-build can
+# still find the host compiler (cmake cache vars are not inherited by
+# subprocess cmake invocations, but env vars are).
 ENV CARGO_TARGET_RISCV64GC_UNKNOWN_LINUX_GNU_LINKER=riscv64-linux-gnu-gcc
 
 # Tell programs to cache in a location that both isn't a `--volume` mounted root