Add Nix configuration files

.github/workflows/deploy.yml

@@ -12,28 +12,28 @@ jobs:
   build:
     name: Build webR
     runs-on: ubuntu-latest
-    container: ghcr.io/r-wasm/webr-flang:main
+    container: ghcr.io/r-wasm/flang-wasm:main
     steps:
+      - uses: actions/checkout@v4
       - uses: actions/setup-node@v3
         with:
           node-version: 'lts/*'
           registry-url: 'https://registry.npmjs.org'
-      - uses: actions/checkout@v3
+      - name: Set npm dist-tag to "next" if pre-release version
+        if: contains(github.ref_name, '-dev') || contains(github.ref_name, '-rc')
+        run: echo "DIST_TAG=next" >> $GITHUB_ENV
       - name: Install required system packages
         run: apt-get update && apt-get install -y gh jq sudo
       - uses: r-lib/actions/setup-r@v2
         with:
           use-public-rspm: true
       - uses: quarto-dev/quarto-actions/setup@v2
-      - name: Install required R packages
+      - name: Install required R packages for building documentation
         run: Rscript -e 'install.packages(c("rmarkdown", "rvest"))'
       - name: Configure webR for flang
+        env:
+          EMFC: /opt/flang/host/bin/flang-new
         run: ./configure
-      - name: Copy flang into webR tree
-        run: |
-          cp -r /opt/flang/wasm .
-          cp -r /opt/flang/host .
-          cp /opt/flang/emfc ./host/bin/emfc
       - name: Setup Emscripten PATH
         run: echo "/opt/emsdk:/opt/emsdk/upstream/emscripten" >> $GITHUB_PATH
       - name: Set Emscripten EM_NODE_JS
@@ -44,7 +44,7 @@ jobs:
       - name: Build all optional wasm libs
         env:
           EMSDK: /opt/emsdk
-        run: cd libs && make all
+        run: cd libs && make all -j
       - name: Build webR
         env:
           EMSDK: /opt/emsdk
@@ -53,6 +53,11 @@ jobs:
       - name: Build webR documentation
         run: cd src/docs && make
         shell: bash
+      - name: Publish to npm
+        if: "!contains(github.ref_name, 'main')"
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+        run: cd src && make publish
       - name: Report code coverage
         uses: codecov/codecov-action@v3
         with:

.github/workflows/test.yml

@@ -7,22 +7,19 @@ on:
   workflow_dispatch:
 
 jobs:
-  build:
+  build-docker:
     runs-on: ubuntu-latest
-    container: ghcr.io/r-wasm/webr-flang:main
+    container: ghcr.io/r-wasm/flang-wasm:main
     steps:
       - uses: actions/setup-node@v3
         with:
           node-version: 'lts/*'
           registry-url: 'https://registry.npmjs.org'
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Configure webR for flang
+        env:
+          EMFC: /opt/flang/host/bin/flang-new
         run: ./configure
-      - name: Copy flang into webR tree
-        run: |
-          cp -r /opt/flang/wasm .
-          cp -r /opt/flang/host .
-          cp /opt/flang/emfc ./host/bin/emfc
       - name: Setup Emscripten PATH
         run: echo "/opt/emsdk:/opt/emsdk/upstream/emscripten" >> $GITHUB_PATH
       - name: Set Emscripten EM_NODE_JS
@@ -41,3 +38,13 @@ jobs:
           fail_ci_if_error: true
           verbose: true
           token: ${{ secrets.CC_TOKEN }}
+  build-nix:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: DeterminateSystems/nix-installer-action@main
+        with:
+          extra-conf: "sandbox = false"
+      - uses: DeterminateSystems/magic-nix-cache-action@main
+      - name: Build Nix package
+        run: nix build --print-build-logs

.gitignore

@@ -11,6 +11,7 @@
 /tools/flang/*llvm-project
 /R/download
 /R/build
+/result
 /src/examples/serve.R
 /src/coverage
 /src/webR/config.[jt]s
@@ -32,3 +33,4 @@ node_modules
 
 /.luarc.json
 /.clangd
+/.emscripten_cache

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "tools/flang"]
+	path = tools/flang
+	url = https://github.com/r-wasm/flang-wasm.git

Makefile

@@ -3,20 +3,17 @@ WASM = $(WEBR_ROOT)/wasm
 HOST = $(WEBR_ROOT)/host
 TOOLS = $(WEBR_ROOT)/tools
 
-# This is symlinked at configure-time
-include $(TOOLS)/fortran.mk
+default: webr
 
-EMFC_FILES = $(EMFC) $(FORTRAN_WASM_LIB)
+# This is created at configure-time
+include $(TOOLS)/fortran.mk
 
 # Build webR and install the web app in `./dist`
 .PHONY: webr
-webr: $(EMFC_FILES) libs
+webr: $(EMFC) $(FORTRAN_WASM_LIB) libs
 	cd R && $(MAKE) && $(MAKE) install
 	cd src && $(MAKE)
 
-$(EMFC_FILES):
-	cd $(EMFC_DIR) && $(MAKE) && $(MAKE) install
-
 # Supporting libs for webr
 .PHONY: libs
 libs:
@@ -49,20 +46,15 @@ check-pr:
 	cd src && $(MAKE) lint && $(MAKE) check && $(MAKE) check-packages
 
 .PHONY: clean
-clean: clean-wasm
-	cd tools/dragonegg && $(MAKE) clean
-	cd tools/flang && $(MAKE) clean
+clean:
+	rm -rf $(HOST) $(WASM)/R-*
+	cd R && $(MAKE) clean
 
 .PHONY: clean-wasm
-clean-wasm: clean-webr
+clean-wasm: clean
 	rm -rf $(WASM)
 	cd libs && $(MAKE) clean
 
-.PHONY: clean-webr
-clean-webr:
-	rm -rf $(HOST) $(WASM)/R-*
-	cd R && $(MAKE) clean
-
 .PHONY: distclean
-distclean: clean
+distclean: clean-wasm clean-tools
 	rm -rf dist

NEWS.md

@@ -1,5 +1,17 @@
 # webR (development version)
 
+## New features
+
+* Support for building webR and LLVM Flang as Nix packages, using Nix flakes.
+
+* WebR's `./configure` script now detects the presence of a `EMFC` environment variable in the user's environment. If this variable points to an existing `flang-new` binary, and a Fortran runtime library for WebAssembly can also be found, webR will skip building LLVM flang and instead use the version provided by the environment.
+
+## Breaking changes
+
+* Upgraded the base LLVM distribution from LLVM 14 to LLVM 17, rebasing our Fortran for WebAssembly patches on the latest release of LLVM at time of writing (v17.0.6). The LLVM Fortran compiler binary name is now `flang-new` and webR's build scripts have been updated to reflect this. The `emfc` wrapper script is no longer required, but for the moment the Make variable pointing to the `flang-new` compiler is still named `EMFC` for backwards compatibility.
+
+* The LLVM flang build scripts are now sourced using a git submodule, to simplify management of CI builds. The build scripts are available at https://github.com/r-wasm/flang-wasm and the patched LLVM source at https://github.com/r-wasm/llvm-project. This allows for an independent build of the patched LLVM flang for WebAssembly, including as a separate Nix package.
+
 # webR 0.2.2
 
 ## New features

R/Makefile

@@ -129,6 +129,7 @@ EXPORTED_RUNTIME_METHODS=[$\
   'allocateUTF8OnStack',$\
   'callMain',$\
   'getValue',$\
+  'getWasmTableEntry',$\
   'setValue'$\
 ]
 
@@ -139,7 +140,6 @@ MAIN_LDFLAGS += -s ALLOW_MEMORY_GROWTH=1
 MAIN_LDFLAGS += -s STACK_SIZE=1MB
 MAIN_LDFLAGS += -s EXIT_RUNTIME=1
 MAIN_LDFLAGS += -s ERROR_ON_UNDEFINED_SYMBOLS=0
-MAIN_LDFLAGS += -s EXPORTED_FUNCTIONS=['getWasmTableEntry']
 MAIN_LDFLAGS += -s EXPORTED_RUNTIME_METHODS=$(EXPORTED_RUNTIME_METHODS)
 MAIN_LDFLAGS += -s FETCH=1
 MAIN_LDFLAGS += -lworkerfs.js -lnodefs.js
@@ -160,7 +160,7 @@ $(BUILD)/state/R-$(R_VERSION)/r-stage2-configured: $(BUILD)/state/R-$(R_VERSION)
 	  CFLAGS="$(STAGE2_CFLAGS)" \
 	  LDFLAGS="$(STAGE2_LDFLAGS)" \
 	  LIBnn="lib" \
-	  FFLAGS="" \
+	  FFLAGS="-fPIC" \
 	  FPICFLAGS="-fPIC" \
 	  FC="$(EMFC)" \
 	  emconfigure ../configure \

README.md

@@ -43,12 +43,18 @@ WebR relies on additional libraries compiled for Wasm for both Cairo graphics su
 If you'd prefer to build all of the available system libraries for Wasm, `cd` into the `libs` directory and run `make all` to build the additional libraries, then finally `cd ..` and run `make clean-webr && make` to rebuild webR. R will automatically detect the additional Wasm libraries and integrate Cairo graphics support as part of the build.
 
 ### Building with Docker
+
 Included in the source repository is a `Dockerfile` which can be used to setup everything that's required for the webR build environment, including LLVM flang and all supported WebAssembly system libraries.
 
 Pre-built docker images can be found in the [GitHub Packages section](https://github.com/r-wasm/webr/pkgs/container/webr). To build the docker image and webR from source, `cd` into the webR source directory then run `docker build .`
 
 The resulting docker image contains a version of R configured to be built for WebAssembly, and so the image can also be used to build custom R packages for webR.
 
+### Building with Nix
+
+If you are using Nix, you can start a development environment by running `nix develop`. Then you can build as usual, with `./configure && make`.
+
+Note that this requires that your Nix installation has support for flakes enabled. The easiest way to do this is to install using the [Nix installer from Determinate Systems](https://zero-to-nix.com/start/install).
 
 ### Node and Emscripten versioning
 

configure

@@ -7,6 +7,9 @@ while [[ $# -gt 0 ]]; do
             USE_DRAGONEGG="true"
             shift
             ;;
+        --with-flang)
+            shift
+            ;;
         *)
             echo "Unknown argument $1"
             exit 1
@@ -16,9 +19,41 @@ done
 
 rm -f tools/fortran.mk
 
-if [ -z ${USE_DRAGONEGG-} ]
-then
-    ln -s fortran-flang.mk tools/fortran.mk
-else
+function configure_emfc {
+    EMFC_ROOT=`dirname ${EMFC}`
+    if [ -f "${FORTRAN_WASM_LIB-}" ]; then
+        EMFC_FLIB=${FORTRAN_WASM_LIB}
+    elif [ -f "${EMFC_ROOT}/../../wasm/lib/libFortranRuntime.a" ]; then
+        EMFC_FLIB=`realpath ${EMFC_ROOT}/../../wasm/lib/libFortranRuntime.a`
+    else
+        echo "Error: Can't find Fortran runtime library."
+        echo "Set FORTRAN_WASM_LIB to the location of libFortranRuntime.a,"\
+            "or unset EMFC to build LLVM flang from source."
+        exit 1
+    fi
+    echo "Found Fortran runtime library: ${EMFC_FLIB}"
+    cat << EOF > tools/fortran.mk
+EMFC = ${EMFC}
+FORTRAN_WASM_LIB = ${EMFC_FLIB}
+FORTRAN_WASM_LDADD = ${EMFC_FLIB}
+.PHONY: clean-tools
+clean-tools:
+	@
+EOF
+}
+
+if [ -n "${USE_DRAGONEGG-}" ]; then
+    # Build dragonegg from source
     ln -s fortran-dragonegg.mk tools/fortran.mk
+elif [ -n "${EMFC-}" ]; then
+    if [ -f "${EMFC-}" ]; then
+        echo "Found Fortran compiler: ${EMFC}"
+        configure_emfc
+    else
+        echo "Error: Can't find Fortran compiler, check EMFC value."
+        exit 1
+    fi
+else
+    # Build LLVM flang from source
+    ln -s fortran-flang.mk tools/fortran.mk
 fi