Set CMAKE_MODULE_PATH in the cmake toolchain file (#335)

Also add some basic testing for the cmake toolchain file.

Fixes: #181

Makefile

@@ -53,7 +53,7 @@ default: build
 check:
 	CC="clang --sysroot=$(BUILD_PREFIX)/share/wasi-sysroot" \
 	CXX="clang++ --sysroot=$(BUILD_PREFIX)/share/wasi-sysroot -fno-exceptions" \
-	PATH="$(PATH_PREFIX)/bin:$$PATH" tests/run.sh $(RUNTIME)
+	PATH="$(PATH_PREFIX)/bin:$$PATH" tests/run.sh "$(BUILD_PREFIX)" "$(RUNTIME)"
 
 clean:
 	rm -rf build $(DESTDIR)
@@ -219,9 +219,10 @@ build/libcxx.BUILT: build/llvm.BUILT build/compiler-rt.BUILT build/wasi-libc.BUI
 build/config.BUILT:
 	mkdir -p $(BUILD_PREFIX)/share/misc
 	cp src/config/config.sub src/config/config.guess $(BUILD_PREFIX)/share/misc
-	mkdir -p $(BUILD_PREFIX)/share/cmake
+	mkdir -p $(BUILD_PREFIX)/share/cmake/Platform
 	cp wasi-sdk.cmake $(BUILD_PREFIX)/share/cmake
 	cp wasi-sdk-pthread.cmake $(BUILD_PREFIX)/share/cmake
+	cp cmake/Platform/WASI.cmake $(BUILD_PREFIX)/share/cmake/Platform
 	touch build/config.BUILT
 
 build: build/llvm.BUILT build/wasi-libc.BUILT build/compiler-rt.BUILT build/libcxx.BUILT build/config.BUILT

tests/cmake/CMakeLists.txt

@@ -0,0 +1,34 @@
+cmake_minimum_required(VERSION 3.22)
+
+project(wasi-sdk-test)
+
+# Sanity check setup
+if (NOT ${CMAKE_SYSTEM_NAME} STREQUAL WASI)
+    message(FATAL_ERROR "Wrong system name (${CMAKE_SYSTEM_NAME}), wrong toolchain file in use?")
+endif()
+
+if(NOT DEFINED WASI)
+    message(FATAL_ERROR "WASI is not set, platform file likely not loaded")
+endif()
+
+set(RUNWASI "" CACHE STRING "Path to or name of WASM runner")
+
+# Test build a C and C++ target respectively
+add_executable(void_main_c ../general/void_main.c)
+add_executable(void_main_cc ../general/void_main.cc)
+
+include(CTest)
+enable_testing()
+
+add_test(NAME void_main_c
+    COMMAND
+        ${CMAKE_CURRENT_SOURCE_DIR}/test_driver.sh
+        ${RUNWASI}
+        $<TARGET_FILE:void_main_c>
+        ${CMAKE_CURRENT_SOURCE_DIR}/../general/void_main.c.stdout.expected)
+add_test(NAME void_main_cc
+    COMMAND
+        ${CMAKE_CURRENT_SOURCE_DIR}/test_driver.sh
+        ${RUNWASI}
+        $<TARGET_FILE:void_main_cc>
+        ${CMAKE_CURRENT_SOURCE_DIR}/../general/void_main.cc.stdout.expected)

tests/cmake/test_driver.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+# Simplified runner for cmake
+
+set -ex
+
+runwasi="$1"
+target="$2"
+stdout_expected="$3"
+stderr_expected="/dev/null"
+
+stdout_observed="$target.stdout.observed"
+stderr_observed="$target.stderr.observed"
+
+"$runwasi" "$target" > "$stdout_observed" 2> "$stderr_observed"
+
+diff -u "$stderr_expected" "$stderr_observed"
+diff -u "$stdout_expected" "$stdout_observed"

tests/run.sh

@@ -1,9 +1,10 @@
 #!/bin/bash
 set -ueo pipefail
 
-# Top-level test runner. Usage is "run.sh" to run tests in compile-only mode,
-# or "run.sh <runwasi>" where <runwasi> is a WASI-capable runtime to run the
-# tests in full compile and execute mode.
+# Top-level test runner. Usage is "run.sh <path to wasi-sdk>" to run tests
+# in compile-only mode, or "run.sh <path to wasi-sdk> <runwasi>" where
+# <runwasi> is a WASI-capable runtime to run the tests in full compile and
+# execute mode.
 #
 # By default this script will look for `clang` and `clang++` in $PATH and
 # assume that they are correctly configured with the sysroot in the default
@@ -12,10 +13,16 @@ set -ueo pipefail
 #  export CXX="<wasi-sdk>/bin/clang++ --sysroot <wasi-sdk>/share/wasi-sysroot"
 #  export CC="<wasi-sdk>/bin/clang --sysroot <wasi-sdk>/share/wasi-sysroot"
 #
+if [ $# -lt 1 ]; then
+    echo "Path to WASI SDK is required"
+    exit 1
+fi
+
+wasi_sdk="$1"
 
 # Determine the wasm runtime to use, if one is provided.
-if [ $# -gt 0 ]; then
-    runwasi="$1"
+if [ $# -gt 1 ]; then
+    runwasi="$2"
 else
     runwasi=""
 fi
@@ -26,6 +33,7 @@ CXX=${CXX:=clang++}
 
 echo $CC
 echo $CXX
+echo "SDK: $wasi_sdk"
 
 cd $testdir/compile-only
 for options in -O0 -O2 "-O2 -flto"; do
@@ -54,3 +62,27 @@ for options in -O0 -O2 "-O2 -flto"; do
     done
 done
 cd - >/dev/null
+
+# Test cmake build system for wasi-sdk
+test_cmake() {
+    local option
+    for option in Debug Release; do
+        rm -rf "$testdir/cmake/build/$option"
+        mkdir -p "$testdir/cmake/build/$option"
+        cd "$testdir/cmake/build/$option"
+        cmake \
+            -G "Unix Makefiles" \
+            -DCMAKE_BUILD_TYPE="$option" \
+            -DRUNWASI="$runwasi" \
+            -DWASI_SDK_PREFIX="$wasi_sdk" \
+            -DCMAKE_TOOLCHAIN_FILE="$wasi_sdk/share/cmake/wasi-sdk.cmake" \
+            ../..
+        make
+        if [[ -n "$runwasi" ]]; then
+            ctest --output-on-failure
+        fi
+        cd - >/dev/null
+    done
+}
+
+test_cmake

wasi-sdk.cmake

@@ -3,6 +3,10 @@
 # This is arbitrary, AFAIK, for now.
 cmake_minimum_required(VERSION 3.4.0)
 
+# Until Platform/WASI.cmake is upstream we need to inject the path to it
+# into CMAKE_MODULE_PATH.
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}")
+
 set(CMAKE_SYSTEM_NAME WASI)
 set(CMAKE_SYSTEM_VERSION 1)
 set(CMAKE_SYSTEM_PROCESSOR wasm32)