Honor $CC and $CXX in test runner (#132)

tests/run.sh

@@ -4,6 +4,14 @@ 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.
+#
+# 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
+# location.  Alternatively, exporting $CC and $CXX allow more flexibility. e.g:
+#
+#  export CXX="<wasi-sdk>/bin/clang++ --sysroot <wasi-sdk>/share/wasi-sysroot"
+#  export CCC="<wasi-sdk>/bin/clang --sysroot <wasi-sdk>/share/wasi-sysroot"
+#
 
 # Determine the wasm runtime to use, if one is provided.
 if [ $# -gt 0 ]; then
@@ -12,30 +20,37 @@ else
     runwasi=""
 fi
 
-cd compile-only
+testdir=$(dirname $0)
+CC=${CC:=clang}
+CXX=${CXX:=clang++}
+
+echo $CC
+echo $CXX
+
+cd $testdir/compile-only
 for options in -O0 -O2 "-O2 -flto"; do
     echo "===== Testing compile-only with $options ====="
     for file in *.c; do
         echo "Testing compile-only $file..."
-        ../testcase.sh "" clang "$options" "$file"
+        ../testcase.sh "" "$CC" "$options" "$file"
     done
     for file in *.cc; do
         echo "Testing compile-only $file..."
-        ../testcase.sh "" clang++ "$options" "$file"
+        ../testcase.sh "" "$CXX" "$options" "$file"
     done
 done
 cd - >/dev/null
 
-cd general
+cd $testdir/general
 for options in -O0 -O2 "-O2 -flto"; do
     echo "===== Testing with $options ====="
     for file in *.c; do
         echo "Testing $file..."
-        ../testcase.sh "$runwasi" clang "$options" "$file"
+        ../testcase.sh "$runwasi" "$CC" "$options" "$file"
     done
     for file in *.cc; do
         echo "Testing $file..."
-        ../testcase.sh "$runwasi" clang++ "$options" "$file"
+        ../testcase.sh "$runwasi" "$CXX" "$options" "$file"
     done
 done
 cd - >/dev/null

tests/testcase.sh

@@ -7,7 +7,7 @@ set -ueo pipefail
 # Command-line parsing; this script is meant to be run from a higher-level
 # script, so don't do anything fancy.
 runwasi="$1"
-clang="$2"
+compiler="$2"
 options="$3"
 input="$4"
 
@@ -27,7 +27,7 @@ fi
 echo "Testing $input..."
 
 # Compile the testcase.
-"$clang" $options $file_options "$input" -o "$wasm"
+$compiler $options $file_options "$input" -o "$wasm"
 
 # If we don't have a runwasi command, we're just doing compile-only testing.
 if [ "$runwasi" == "" ]; then