Remove remnants of malloc.cc

This was removed in
https://boringssl-review.googlesource.com/c/boringssl/+/56925

Change-Id: Id55859b26b7a87d77586c7b27008d07fe12a499a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/61306
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
diff --git a/ssl/test/PORTING.md b/ssl/test/PORTING.md
index 74280b2..c99cdbc 100644
--- a/ssl/test/PORTING.md
+++ b/ssl/test/PORTING.md
@@ -99,7 +99,10 @@
 enough calls to reach the number, the shim should fail with exit code
 `88`. This signals to the runner that the test has completed.
 
-See `crypto/test/malloc.cc` for an example malloc implementation.
+Historically, BoringSSL did this by replacing the actual `malloc`
+symbol, but we have found hooking the library's `malloc` wrapper, under a
+test-only build configuration, to be more straightforward. See `crypto/mem.c`
+for an example which handles the environment variables in `OPENSSL_malloc`.
 
 Note these tests are slow and will hit Go's test timeout. Pass `-timeout 72h` to
 avoid crashing after 10 minutes.
diff --git a/util/generate_build_files.py b/util/generate_build_files.py
index 642d4d5..c6ddf28 100644
--- a/util/generate_build_files.py
+++ b/util/generate_build_files.py
@@ -276,8 +276,6 @@
                              files['test_support_headers'] +
                              files['crypto_internal_headers'] +
                              files['ssl_internal_headers']):
-        if os.path.basename(filename) == 'malloc.cc':
-          continue
         out.write('    "%s",\n' % PathOf(filename))
 
       out.write(']\n')