test_runner: add amcheck to test_compatibility (#4772)

Run `pg_amcheck` in forward and backward compatibility tests to catch
some data corruption.

## Summary of changes
- Add amcheck compiling to Makefile
- Add `pg_amcheck` to test_compatibility

Makefile

@@ -108,6 +108,8 @@ postgres-%: postgres-configure-% \
 	$(MAKE) -C $(POSTGRES_INSTALL_DIR)/build/$*/contrib/pg_buffercache install
 	+@echo "Compiling pageinspect $*"
 	$(MAKE) -C $(POSTGRES_INSTALL_DIR)/build/$*/contrib/pageinspect install
+	+@echo "Compiling amcheck $*"
+	$(MAKE) -C $(POSTGRES_INSTALL_DIR)/build/$*/contrib/amcheck install
 
 .PHONY: postgres-clean-%
 postgres-clean-%:

test_runner/regress/test_compatibility.py

@@ -438,6 +438,14 @@ def check_neon_works(
         test_output_dir / "dump-from-wal.filediff",
     )
 
+    # TODO: Run pg_amcheck unconditionally after the next release
+    try:
+        pg_bin.run(["psql", connstr, "--command", "CREATE EXTENSION IF NOT EXISTS amcheck"])
+    except subprocess.CalledProcessError:
+        log.info("Extension amcheck is not available, skipping pg_amcheck")
+    else:
+        pg_bin.run_capture(["pg_amcheck", connstr, "--install-missing", "--verbose"])
+
     # Check that we can interract with the data
     pg_bin.run_capture(["pgbench", "--time=10", "--progress=2", connstr])