Log cc1 calls instead of deleting cc1

Author: EliahKagan

.github/workflows/ci.yml

@@ -40,7 +40,7 @@ jobs:
           apt-get update
           apt-get install --no-install-recommends -y -- "${prerequisites[@]}"
         shell: bash
-      - name: Verify environment is sufficiently minimal for the test
+      - name: Verify that we are in an environment with minimal dev tools
         run: |
           set -x
           for pattern in cmake g++ libssl-dev make pkgconf pkg-config; do
@@ -64,14 +64,32 @@ jobs:
           pattern='.*\b(-sys|cc|cmake|pkg-config|vcpkg)\b.*'
           ! GREP_COLORS='ms=30;48;5;214' grep --color=always -Ex -C 1000000 -e "$pattern" tree.txt
         continue-on-error: true
-      - name: Do max-pure build with minimal environment
-        run: cargo install --debug --locked --no-default-features --features max-pure --path .
-      - name: Clear target
-        run: cargo clean
-      - name: Break GCC's ability to compile C or C++
-        run: find /usr/lib/gcc \( -name cc1 -o -name cc1plus \) -print -delete
-      - name: Do max-pure build without being able to compile C or C++
+      - name: Wrap cc1 (and cc1plus if present) to record calls
+        run: |
+          cat >/usr/local/bin/wrapper1 <<'EOF'
+          #!/bin/sh
+          printf '%s %s\n' "$0" "$*" >>/var/log/wrapper1.log
+          exec "$0.orig" "$@"
+          EOF
+
+          cat >/usr/local/bin/wrap1 <<'EOF'
+          #!/bin/sh -e
+          dir="$(dirname -- "$1")"
+          base="$(basename -- "$1")"
+          cd -- "$dir"
+          mv -- "$base" "$base.orig"
+          ln -s -- /usr/local/bin/wrapper1 "$base"
+          EOF
+
+          chmod +x /usr/local/bin/wrap1 /usr/local/bin/wrapper1
+
+          find /usr/lib/gcc \( -name cc1 -o -name cc1plus \) \
+            -print -exec /usr/local/bin/wrap1 {} \;
+      - name: Build max-pure with minimal dev tools and log cc1
         run: cargo install --debug --locked --no-default-features --features max-pure --path .
+      - name: Show logged C and C++ compilations (should be none)
+        run: |
+          ! cat /var/log/wrapper1.log
         continue-on-error: true
 
   test: