Direct call to eval passes strict mode through.

src/compiler.cc

Index: src/compiler.cc
diff --git a/src/compiler.cc b/src/compiler.cc
index 5c18c3e53ebc8d6d3eb2dfc0e36301481621d20d..77111a842e7d55e6aa4a7ea8dfa02635ee431f3c 100755
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -548,7 +548,8 @@ Handle<SharedFunctionInfo> Compiler::Compile(Handle<String> source,
 
 Handle<SharedFunctionInfo> Compiler::CompileEval(Handle<String> source,
                                                  Handle<Context> context,
-                                                 bool is_global) {
+                                                 bool is_global,
+                                                 StrictModeFlag strict_mode) {
   int source_length = source->length();
   Counters::total_eval_size.Increment(source_length);
   Counters::total_compile_size.Increment(source_length);
@@ -559,7 +560,10 @@ Handle<SharedFunctionInfo> Compiler::CompileEval(Handle<String> source,
   // Do a lookup in the compilation cache; if the entry is not there, invoke
   // the compiler and add the result to the cache.
   Handle<SharedFunctionInfo> result;
-  result = CompilationCache::LookupEval(source, context, is_global);
+  result = CompilationCache::LookupEval(source,
+                                        context,
+                                        is_global,
+                                        strict_mode);
 
   if (result.is_null()) {
     // Create a script object describing the script to be compiled.
@@ -567,9 +571,14 @@ Handle<SharedFunctionInfo> Compiler::CompileEval(Handle<String> source,
     CompilationInfo info(script);
     info.MarkAsEval();
     if (is_global) info.MarkAsGlobal();
+    if (strict_mode == kStrictMode) info.MarkAsStrict();
     info.SetCallingContext(context);
     result = MakeFunctionInfo(&info);
     if (!result.is_null()) {
+      // If caller is strict mode, the result must be strict as well,
+      // but not the other way around. Consider:
+      // eval("'use strict'; ...");
+      ASSERT(strict_mode == kNonStrictMode || result->strict_mode());
       CompilationCache::PutEval(source, context, is_global, result);
     }
   }
@@ -762,6 +771,7 @@ void Compiler::SetFunctionInfo(Handle<SharedFunctionInfo> function_info,
       *lit->this_property_assignments());
   function_info->set_try_full_codegen(lit->try_full_codegen());
   function_info->set_allows_lazy_compilation(lit->AllowsLazyCompilation());
+  function_info->set_strict_mode(lit->strict_mode());
 }