Generate ccache wrapper scripts instead of symlink (#39)

Tested with Bazel 5.2. It is a workaround for issue
bazelbuild/rules_cc#130

scripts/codebase_utils.sh

@@ -13,5 +13,6 @@ export CRIS_CODE_DIRS="$(sed 's/^[[:space:]]*//' <<< "
 " | grep '[^[:space:]]')"
 
 function bazel_common_all () {
-    bazel "$@" '//...'
+    # Need to set PATH instead of CC because Bazel does not like '/'s in the CC value.
+    PATH="$(dirname "$CC"):$PATH" CC="$(basename "$CC")" bazel "$@" '//...'
 }

scripts/toolchain.sh

@@ -14,10 +14,20 @@ pushd "$(dirname "$0")/.."
 if which ccache >/dev/null 2>&1 && ([ -d 'run' ] && [ -w 'run' ] || [ -w '.' ]); then
     rm -rf 'run/toolchain'
     mkdir -p 'run/toolchain'
-    ln -sf "$(which ccache)" "run/toolchain/$CC"
-    ln -sf "$(which ccache)" "run/toolchain/$CXX"
-    export CC="$( realpath -e "run/toolchain")/$CC"
-    export CXX="$(realpath -e "run/toolchain")/$CXX"
+    CR_CCACHE_CC_DIR="$(realpath -e "run/toolchain")"
+
+    for compiler_varname in "CC"; do
+        compiler="$(eval echo "\$$compiler_varname")"
+        ccache_wrapper="$CR_CCACHE_CC_DIR/$(basename "$compiler")"
+        # Bazel may dereference the ccache symlink, so we use wrapper scripts instead.
+        # See https://github.com/bazelbuild/rules_cc/issues/130
+        cat << ____________EOF | sed 's/^            //' > "$ccache_wrapper"
+            #!/bin/bash
+            '$(which ccache)' '$(which "$compiler")' "\$@"
+____________EOF
+        chmod +x "$ccache_wrapper"
+        eval "export $compiler_varname='$ccache_wrapper'"
+    done
 fi
 
 popd