Fix aggressive params file assumption

keith · copybara-github · commit 24e82426e689 · 2022-02-22T06:23:32.000-08:00
Most programs that accept params files use the `@file` syntax. For Apple platform builds `@` can be the start of non-params file arguments as well, such as `-rpath @executable_path/Frameworks`. There is a small list of options where this is the case, so this new behavior no longer assumes params files if args start with `@`, they also have to not start with one of the 3 keywords used with this (from `man dyld` on macOS). This should always hold since params files generated by bazel should always start with `bazel-out`, if someone renames the symlinks to one of the keywords, they're on their own. Previously the workaround was to always make sure to pass the `-Wl,-rpath,@executable_path` form of these arguments, but this makes users not have to worry about this. In a few other places we check this by checking if the file exists, which is likely more accurate, but feels excessive and potentially dangerous in this context. Related: bazelbuild#13148 Fixes: bazelbuild#14316 Closes bazelbuild#14650. PiperOrigin-RevId: 430195929
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/LinkCommandLine.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/LinkCommandLine.java
@@ -270,36 +270,43 @@ CommandLine paramCmdLine() {
         paramFile, linkTargetType, forcedToolPath, featureConfiguration, actionName, variables);
   }
 
-  public static void extractArgumentsForStaticLinkParamFile(
+  private static void extractArgumentsForStaticLinkParamFile(
       List<String> args, List<String> commandlineArgs, List<String> paramFileArgs) {
     commandlineArgs.add(args.get(0)); // ar command, must not be moved!
     int argsSize = args.size();
     for (int i = 1; i < argsSize; i++) {
       String arg = args.get(i);
-      if (arg.startsWith("@")) {
+      if (isLikelyParamFile(arg)) {
         commandlineArgs.add(arg); // params file, keep it in the command line
       } else {
         paramFileArgs.add(arg); // the rest goes to the params file
       }
     }
   }
 
-  public static void extractArgumentsForDynamicLinkParamFile(
+  private static void extractArgumentsForDynamicLinkParamFile(
       List<String> args, List<String> commandlineArgs, List<String> paramFileArgs) {
     // Note, that it is not important that all linker arguments are extracted so that
     // they can be moved into a parameter file, but the vast majority should.
     commandlineArgs.add(args.get(0)); // gcc command, must not be moved!
     int argsSize = args.size();
     for (int i = 1; i < argsSize; i++) {
       String arg = args.get(i);
-      if (arg.startsWith("@")) {
+      if (isLikelyParamFile(arg)) {
         commandlineArgs.add(arg); // params file, keep it in the command line
       } else {
         paramFileArgs.add(arg); // the rest goes to the params file
       }
     }
   }
 
+  private static boolean isLikelyParamFile(String arg) {
+    return arg.startsWith("@")
+        && !arg.startsWith("@rpath")
+        && !arg.startsWith("@loader_path")
+        && !arg.startsWith("@executable_path");
+  }
+
   /**
    * Returns a raw link command for the given link invocation, including both command and arguments
    * (argv). The version that uses the expander is preferred, but that one can't be used during
