From 9829f188b7f8b0b31e34bee8b1827131ab34324f Mon Sep 17 00:00:00 2001
From: Jon Meow <46229924+jonmeow@users.noreply.github.com>
Date: Mon, 2 Aug 2021 11:08:22 -0700
Subject: [PATCH] Move all new's to global_arena, and remove ASAN disabling
 (#690)

Note this changes identifiers from char* to string to avoid malloc.

Fixes #580
---
 executable_semantics/BUILD                    |  8 ----
 executable_semantics/ast/BUILD                | 10 +----
 executable_semantics/ast/member.cpp           |  4 +-
 executable_semantics/ast/pattern.cpp          |  9 ++--
 executable_semantics/ast/pattern_test.cpp     | 17 ++++----
 executable_semantics/ast/statement.cpp        | 29 +++++++------
 executable_semantics/common/arena.h           |  2 +-
 executable_semantics/interpreter/BUILD        |  5 +++
 executable_semantics/interpreter/action.cpp   | 11 ++---
 executable_semantics/interpreter/dictionary.h |  4 +-
 .../interpreter/interpreter.cpp               | 35 ++++++++-------
 .../interpreter/typecheck.cpp                 | 24 +++++++----
 executable_semantics/interpreter/value.cpp    | 43 ++++++++++---------
 executable_semantics/syntax/BUILD             |  1 +
 executable_semantics/syntax/lexer.lpp         |  5 +--
 executable_semantics/syntax/parser.ypp        | 36 ++++++++--------
 .../syntax/syntax_helpers.cpp                 |  3 +-
 executable_semantics/tests.py                 |  4 --
 18 files changed, 130 insertions(+), 120 deletions(-)

diff --git a/executable_semantics/BUILD b/executable_semantics/BUILD
index d0f8af7d0475..ed0b57fd836c 100644
--- a/executable_semantics/BUILD
+++ b/executable_semantics/BUILD
@@ -26,10 +26,6 @@ cc_binary(
         ":executable_semantics",
         "testdata/%s.carbon" % e,
     ],
-    env = {
-        # TODO(#580): Remove this when leaks are fixed.
-        "ASAN_OPTIONS": "detect_leaks=0",
-    },
     golden = "testdata/%s.golden" % e,
 ) for e in TEST_LIST]
 
@@ -49,10 +45,6 @@ test_suite(
         ":executable_semantics",
         "testdata/%s.carbon" % e,
     ],
-    env = {
-        # TODO(#580): Remove this when leaks are fixed.
-        "ASAN_OPTIONS": "detect_leaks=0",
-    },
     golden = "testdata/%s.golden" % e,
     golden_is_subset = True,
 ) for e in TEST_LIST]
diff --git a/executable_semantics/ast/BUILD b/executable_semantics/ast/BUILD
index fc99bc251999..a7e24a4c179e 100644
--- a/executable_semantics/ast/BUILD
+++ b/executable_semantics/ast/BUILD
@@ -42,10 +42,6 @@ cc_library(
 cc_test(
     name = "expression_test",
     srcs = ["expression_test.cpp"],
-    env = {
-        # TODO(#580): Remove this when leaks are fixed.
-        "ASAN_OPTIONS": "detect_leaks=0",
-    },
     deps = [
         ":expression",
         "//executable_semantics/syntax:paren_contents",
@@ -82,6 +78,7 @@ cc_library(
     deps = [
         ":expression",
         "//common:ostream",
+        "//executable_semantics/common:arena",
         "//executable_semantics/common:error",
         "@llvm-project//llvm:Support",
     ],
@@ -90,10 +87,6 @@ cc_library(
 cc_test(
     name = "pattern_test",
     srcs = ["pattern_test.cpp"],
-    env = {
-        # TODO(#580): Remove this when leaks are fixed.
-        "ASAN_OPTIONS": "detect_leaks=0",
-    },
     deps = [
         ":pattern",
         "//executable_semantics/syntax:paren_contents",
@@ -112,6 +105,7 @@ cc_library(
         ":pattern",
         "//common:check",
         "//common:ostream",
+        "//executable_semantics/common:arena",
         "@llvm-project//llvm:Support",
     ],
 )
diff --git a/executable_semantics/ast/member.cpp b/executable_semantics/ast/member.cpp
index b7b14a24f429..293440277cf6 100644
--- a/executable_semantics/ast/member.cpp
+++ b/executable_semantics/ast/member.cpp
@@ -4,11 +4,13 @@
 
 #include "executable_semantics/ast/member.h"
 
+#include "executable_semantics/common/arena.h"
+
 namespace Carbon {
 
 auto Member::MakeFieldMember(int line_num, const BindingPattern* binding)
     -> Member* {
-  auto m = new Member();
+  auto m = global_arena->New<Member>();
   m->line_num = line_num;
   m->value = FieldMember({.binding = binding});
   return m;
diff --git a/executable_semantics/ast/pattern.cpp b/executable_semantics/ast/pattern.cpp
index 2d608a10bbe3..7a429b290bb4 100644
--- a/executable_semantics/ast/pattern.cpp
+++ b/executable_semantics/ast/pattern.cpp
@@ -8,6 +8,7 @@
 
 #include "common/ostream.h"
 #include "executable_semantics/ast/expression.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/common/error.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/Casting.h"
@@ -57,7 +58,8 @@ TuplePattern::TuplePattern(const Expression* tuple_literal)
     : Pattern(Kind::TuplePattern, tuple_literal->line_num) {
   const auto& tuple = tuple_literal->GetTupleLiteral();
   for (const FieldInitializer& init : tuple.fields) {
-    fields.push_back(Field(init.name, new ExpressionPattern(init.expression)));
+    fields.push_back(Field(
+        init.name, global_arena->New<ExpressionPattern>(init.expression)));
   }
 }
 
@@ -75,7 +77,7 @@ auto PatternFromParenContents(int line_num,
 auto TuplePatternFromParenContents(int line_num,
                                    const ParenContents<Pattern>& paren_contents)
     -> const TuplePattern* {
-  return new TuplePattern(
+  return global_arena->New<TuplePattern>(
       line_num, paren_contents.TupleElements<TuplePattern::Field>(line_num));
 }
 
@@ -98,7 +100,8 @@ auto ParenExpressionToParenPattern(const ParenContents<Expression>& contents)
       .elements = {}, .has_trailing_comma = contents.has_trailing_comma};
   for (const auto& element : contents.elements) {
     result.elements.push_back(
-        {.name = element.name, .term = new ExpressionPattern(element.term)});
+        {.name = element.name,
+         .term = global_arena->New<ExpressionPattern>(element.term)});
   }
   return result;
 }
diff --git a/executable_semantics/ast/pattern_test.cpp b/executable_semantics/ast/pattern_test.cpp
index 1c53e5a3a5f8..94bfc0025f62 100644
--- a/executable_semantics/ast/pattern_test.cpp
+++ b/executable_semantics/ast/pattern_test.cpp
@@ -5,6 +5,7 @@
 #include "executable_semantics/ast/pattern.h"
 
 #include "executable_semantics/ast/expression.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/syntax/paren_contents.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
@@ -51,7 +52,7 @@ TEST(PatternTest, UnaryNoCommaAsPattern) {
   // ```
   ParenContents<Pattern> contents = {
       .elements = {{.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/2)}},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/2)}},
       .has_trailing_comma = false};
 
   const Pattern* pattern = PatternFromParenContents(/*line_num=*/1, contents);
@@ -62,7 +63,7 @@ TEST(PatternTest, UnaryNoCommaAsPattern) {
 TEST(PatternTest, UnaryNoCommaAsTuplePattern) {
   ParenContents<Pattern> contents = {
       .elements = {{.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/2)}},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/2)}},
       .has_trailing_comma = false};
 
   const TuplePattern* tuple =
@@ -74,7 +75,7 @@ TEST(PatternTest, UnaryNoCommaAsTuplePattern) {
 TEST(PatternTest, UnaryWithCommaAsPattern) {
   ParenContents<Pattern> contents = {
       .elements = {{.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/2)}},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/2)}},
       .has_trailing_comma = true};
 
   const Pattern* pattern = PatternFromParenContents(/*line_num=*/1, contents);
@@ -87,7 +88,7 @@ TEST(PatternTest, UnaryWithCommaAsPattern) {
 TEST(PatternTest, UnaryWithCommaAsTuplePattern) {
   ParenContents<Pattern> contents = {
       .elements = {{.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/2)}},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/2)}},
       .has_trailing_comma = true};
 
   const TuplePattern* tuple =
@@ -99,9 +100,9 @@ TEST(PatternTest, UnaryWithCommaAsTuplePattern) {
 TEST(PatternTest, BinaryAsPattern) {
   ParenContents<Pattern> contents = {
       .elements = {{.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/2)},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/2)},
                    {.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/3)}},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/3)}},
       .has_trailing_comma = true};
 
   const Pattern* pattern = PatternFromParenContents(/*line_num=*/1, contents);
@@ -114,9 +115,9 @@ TEST(PatternTest, BinaryAsPattern) {
 TEST(PatternTest, BinaryAsTuplePattern) {
   ParenContents<Pattern> contents = {
       .elements = {{.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/2)},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/2)},
                    {.name = std::nullopt,
-                    .term = new AutoPattern(/*line_num=*/3)}},
+                    .term = global_arena->New<AutoPattern>(/*line_num=*/3)}},
       .has_trailing_comma = true};
 
   const TuplePattern* tuple =
diff --git a/executable_semantics/ast/statement.cpp b/executable_semantics/ast/statement.cpp
index 02446b5090be..05cbb0d05573 100644
--- a/executable_semantics/ast/statement.cpp
+++ b/executable_semantics/ast/statement.cpp
@@ -5,6 +5,7 @@
 #include "executable_semantics/ast/statement.h"
 
 #include "common/check.h"
+#include "executable_semantics/common/arena.h"
 
 namespace Carbon {
 
@@ -62,7 +63,7 @@ auto Statement::GetAwait() const -> const Await& {
 
 auto Statement::MakeExpressionStatement(int line_num, const Expression* exp)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = ExpressionStatement({.exp = exp});
   return s;
@@ -70,7 +71,7 @@ auto Statement::MakeExpressionStatement(int line_num, const Expression* exp)
 
 auto Statement::MakeAssign(int line_num, const Expression* lhs,
                            const Expression* rhs) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Assign({.lhs = lhs, .rhs = rhs});
   return s;
@@ -79,7 +80,7 @@ auto Statement::MakeAssign(int line_num, const Expression* lhs,
 auto Statement::MakeVariableDefinition(int line_num, const Pattern* pat,
                                        const Expression* init)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = VariableDefinition({.pat = pat, .init = init});
   return s;
@@ -88,7 +89,7 @@ auto Statement::MakeVariableDefinition(int line_num, const Pattern* pat,
 auto Statement::MakeIf(int line_num, const Expression* cond,
                        const Statement* then_stmt, const Statement* else_stmt)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = If({.cond = cond, .then_stmt = then_stmt, .else_stmt = else_stmt});
   return s;
@@ -96,21 +97,21 @@ auto Statement::MakeIf(int line_num, const Expression* cond,
 
 auto Statement::MakeWhile(int line_num, const Expression* cond,
                           const Statement* body) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = While({.cond = cond, .body = body});
   return s;
 }
 
 auto Statement::MakeBreak(int line_num) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Break();
   return s;
 }
 
 auto Statement::MakeContinue(int line_num) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Continue();
   return s;
@@ -118,7 +119,7 @@ auto Statement::MakeContinue(int line_num) -> const Statement* {
 
 auto Statement::MakeReturn(int line_num, const Expression* e)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Return({.exp = e});
   return s;
@@ -126,7 +127,7 @@ auto Statement::MakeReturn(int line_num, const Expression* e)
 
 auto Statement::MakeSequence(int line_num, const Statement* s1,
                              const Statement* s2) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Sequence({.stmt = s1, .next = s2});
   return s;
@@ -134,7 +135,7 @@ auto Statement::MakeSequence(int line_num, const Statement* s1,
 
 auto Statement::MakeBlock(int line_num, const Statement* stmt)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Block({.stmt = stmt});
   return s;
@@ -144,7 +145,7 @@ auto Statement::MakeMatch(
     int line_num, const Expression* exp,
     std::list<std::pair<const Pattern*, const Statement*>>* clauses)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Match({.exp = exp, .clauses = clauses});
   return s;
@@ -155,7 +156,7 @@ auto Statement::MakeMatch(
 auto Statement::MakeContinuation(int line_num,
                                  std::string continuation_variable,
                                  const Statement* body) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value =
       Continuation({.continuation_variable = std::move(continuation_variable),
@@ -166,7 +167,7 @@ auto Statement::MakeContinuation(int line_num,
 // Returns an AST node for a run statement give its line number and argument.
 auto Statement::MakeRun(int line_num, const Expression* argument)
     -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Run({.argument = argument});
   return s;
@@ -174,7 +175,7 @@ auto Statement::MakeRun(int line_num, const Expression* argument)
 
 // Returns an AST node for an await statement give its line number.
 auto Statement::MakeAwait(int line_num) -> const Statement* {
-  auto* s = new Statement();
+  auto* s = global_arena->New<Statement>();
   s->line_num = line_num;
   s->value = Await();
   return s;
diff --git a/executable_semantics/common/arena.h b/executable_semantics/common/arena.h
index b1bd68b3c425..b42e4b02c7d8 100644
--- a/executable_semantics/common/arena.h
+++ b/executable_semantics/common/arena.h
@@ -37,7 +37,7 @@ class Arena {
   class ArenaEntryTyped : public ArenaEntry {
    public:
     template <typename... Args>
-    explicit ArenaEntryTyped(Args&... args)
+    explicit ArenaEntryTyped(Args&&... args)
         : instance(std::forward<Args>(args)...) {}
 
     auto Instance() -> T* { return &instance; }
diff --git a/executable_semantics/interpreter/BUILD b/executable_semantics/interpreter/BUILD
index a40d659c8ba5..a2955fce1619 100644
--- a/executable_semantics/interpreter/BUILD
+++ b/executable_semantics/interpreter/BUILD
@@ -17,6 +17,7 @@ cc_library(
         "//executable_semantics/ast:expression",
         "//executable_semantics/ast:function_definition",
         "//executable_semantics/ast:statement",
+        "//executable_semantics/common:arena",
         "@llvm-project//llvm:Support",
     ],
 )
@@ -97,6 +98,7 @@ cc_library(
         "//executable_semantics/ast:declaration",
         "//executable_semantics/ast:expression",
         "//executable_semantics/ast:function_definition",
+        "//executable_semantics/common:arena",
         "//executable_semantics/common:tracing_flag",
         "@llvm-project//llvm:Support",
     ],
@@ -113,6 +115,7 @@ cc_library(
         "//executable_semantics/ast:expression",
         "//executable_semantics/ast:function_definition",
         "//executable_semantics/ast:statement",
+        "//executable_semantics/common:arena",
         "//executable_semantics/common:tracing_flag",
         "@llvm-project//llvm:Support",
     ],
@@ -129,6 +132,8 @@ cc_library(
         "//common:ostream",
         "//executable_semantics/ast:function_definition",
         "//executable_semantics/ast:statement",
+        "//executable_semantics/common:arena",
+        "//executable_semantics/common:error",
         "@llvm-project//llvm:Support",
     ],
 )
diff --git a/executable_semantics/interpreter/action.cpp b/executable_semantics/interpreter/action.cpp
index c73161b548c5..dad17615d43a 100644
--- a/executable_semantics/interpreter/action.cpp
+++ b/executable_semantics/interpreter/action.cpp
@@ -12,37 +12,38 @@
 
 #include "executable_semantics/ast/expression.h"
 #include "executable_semantics/ast/function_definition.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/interpreter/stack.h"
 #include "llvm/ADT/StringExtras.h"
 
 namespace Carbon {
 
 auto Action::MakeLValAction(const Expression* e) -> Action* {
-  auto* act = new Action();
+  auto* act = global_arena->New<Action>();
   act->value = LValAction({.exp = e});
   return act;
 }
 
 auto Action::MakeExpressionAction(const Expression* e) -> Action* {
-  auto* act = new Action();
+  auto* act = global_arena->New<Action>();
   act->value = ExpressionAction({.exp = e});
   return act;
 }
 
 auto Action::MakePatternAction(const Pattern* p) -> Action* {
-  auto* act = new Action();
+  auto* act = global_arena->New<Action>();
   act->value = PatternAction({.pattern = p});
   return act;
 }
 
 auto Action::MakeStatementAction(const Statement* s) -> Action* {
-  auto* act = new Action();
+  auto* act = global_arena->New<Action>();
   act->value = StatementAction({.stmt = s});
   return act;
 }
 
 auto Action::MakeValAction(const Value* v) -> Action* {
-  auto* act = new Action();
+  auto* act = global_arena->New<Action>();
   act->value = ValAction({.val = v});
   return act;
 }
diff --git a/executable_semantics/interpreter/dictionary.h b/executable_semantics/interpreter/dictionary.h
index 4cec806a0984..136d51ee2454 100644
--- a/executable_semantics/interpreter/dictionary.h
+++ b/executable_semantics/interpreter/dictionary.h
@@ -10,6 +10,7 @@
 #include <optional>
 #include <string>
 
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/interpreter/list_node.h"
 
 namespace Carbon {
@@ -37,7 +38,8 @@ class Dictionary {
   // Associate the value v with key k in the dictionary.
   // Time complexity: O(1).
   auto Set(const K& k, const V& v) -> void {
-    head = new ListNode<std::pair<K, V>>(std::make_pair(k, v), head);
+    head = global_arena->New<ListNode<std::pair<K, V>>>(std::make_pair(k, v),
+                                                        head);
   }
 
   typedef ListNodeIterator<std::pair<K, V>> Iterator;
diff --git a/executable_semantics/interpreter/interpreter.cpp b/executable_semantics/interpreter/interpreter.cpp
index 4e6fc2841fde..9ad47b3a8ae3 100644
--- a/executable_semantics/interpreter/interpreter.cpp
+++ b/executable_semantics/interpreter/interpreter.cpp
@@ -14,6 +14,7 @@
 #include "common/check.h"
 #include "executable_semantics/ast/expression.h"
 #include "executable_semantics/ast/function_definition.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/common/error.h"
 #include "executable_semantics/common/tracing_flag.h"
 #include "executable_semantics/interpreter/action.h"
@@ -193,10 +194,11 @@ void CallFunction(int line_num, std::vector<const Value*> operas,
                        &params, line_num);
       CHECK(matches) << "internal error in call_function, pattern match failed";
       // Create the new frame and push it on the stack
-      auto* scope = new Scope(*matches, params);
-      auto* frame = new Frame(operas[0]->GetFunctionValue().name, Stack(scope),
-                              Stack(Action::MakeStatementAction(
-                                  operas[0]->GetFunctionValue().body)));
+      auto* scope = global_arena->New<Scope>(*matches, params);
+      auto* frame = global_arena->New<Frame>(
+          operas[0]->GetFunctionValue().name, Stack(scope),
+          Stack(
+              Action::MakeStatementAction(operas[0]->GetFunctionValue().body)));
       state->stack.Push(frame);
       break;
     }
@@ -888,7 +890,7 @@ void StepStmt() {
           std::optional<Env> matches =
               PatternMatch(pat, v, values, &vars, stmt->line_num);
           if (matches) {  // we have a match, start the body
-            auto* new_scope = new Scope(*matches, vars);
+            auto* new_scope = global_arena->New<Scope>(*matches, vars);
             frame->scopes.Push(new_scope);
             const Statement* body_block =
                 Statement::MakeBlock(stmt->line_num, c->second);
@@ -959,7 +961,8 @@ void StepStmt() {
     case StatementKind::Block: {
       if (act->pos == 0) {
         if (stmt->GetBlock().stmt) {
-          auto* scope = new Scope(CurrentEnv(state), {});
+          auto* scope = global_arena->New<Scope>(CurrentEnv(state),
+                                                 std::list<std::string>());
           frame->scopes.Push(scope);
           frame->todo.Push(Action::MakeStatementAction(stmt->GetBlock().stmt));
           act->pos++;
@@ -1085,14 +1088,16 @@ void StepStmt() {
       CHECK(act->pos == 0);
       // Create a continuation object by creating a frame similar the
       // way one is created in a function call.
-      Scope* scope = new Scope(CurrentEnv(state), std::list<std::string>());
+      Scope* scope =
+          global_arena->New<Scope>(CurrentEnv(state), std::list<std::string>());
       Stack<Scope*> scopes;
       scopes.Push(scope);
       Stack<Action*> todo;
       todo.Push(Action::MakeStatementAction(Statement::MakeReturn(
           stmt->line_num, Expression::MakeTupleLiteral(stmt->line_num, {}))));
       todo.Push(Action::MakeStatementAction(stmt->GetContinuation().body));
-      Frame* continuation_frame = new Frame("__continuation", scopes, todo);
+      Frame* continuation_frame =
+          global_arena->New<Frame>("__continuation", scopes, todo);
       Address continuation_address = state->heap.AllocateValue(
           Value::MakeContinuationValue({continuation_frame}));
       // Store the continuation's address in the frame.
@@ -1176,7 +1181,7 @@ void Step() {
 
 // Interpret the whole porogram.
 auto InterpProgram(std::list<Declaration>* fs) -> int {
-  state = new State();  // Runtime state.
+  state = global_arena->New<State>();  // Runtime state.
   if (tracing_output) {
     llvm::outs() << "********** initializing globals **********\n";
   }
@@ -1186,8 +1191,8 @@ auto InterpProgram(std::list<Declaration>* fs) -> int {
   const Expression* call_main = Expression::MakeCallExpression(
       0, Expression::MakeIdentifierExpression(0, "main"), arg);
   auto todo = Stack(Action::MakeExpressionAction(call_main));
-  auto* scope = new Scope(globals, std::list<std::string>());
-  auto* frame = new Frame("top", Stack(scope), todo);
+  auto* scope = global_arena->New<Scope>(globals, std::list<std::string>());
+  auto* frame = global_arena->New<Frame>("top", Stack(scope), todo);
   state->stack = Stack(frame);
 
   if (tracing_output) {
@@ -1209,8 +1214,8 @@ auto InterpProgram(std::list<Declaration>* fs) -> int {
 // Interpret an expression at compile-time.
 auto InterpExp(Env values, const Expression* e) -> const Value* {
   auto todo = Stack(Action::MakeExpressionAction(e));
-  auto* scope = new Scope(values, std::list<std::string>());
-  auto* frame = new Frame("InterpExp", Stack(scope), todo);
+  auto* scope = global_arena->New<Scope>(values, std::list<std::string>());
+  auto* frame = global_arena->New<Frame>("InterpExp", Stack(scope), todo);
   state->stack = Stack(frame);
 
   while (state->stack.Count() > 1 || state->stack.Top()->todo.Count() > 1 ||
@@ -1224,8 +1229,8 @@ auto InterpExp(Env values, const Expression* e) -> const Value* {
 // Interpret a pattern at compile-time.
 auto InterpPattern(Env values, const Pattern* p) -> const Value* {
   auto todo = Stack(Action::MakePatternAction(p));
-  auto* scope = new Scope(values, std::list<std::string>());
-  auto* frame = new Frame("InterpPattern", Stack(scope), todo);
+  auto* scope = global_arena->New<Scope>(values, std::list<std::string>());
+  auto* frame = global_arena->New<Frame>("InterpPattern", Stack(scope), todo);
   state->stack = Stack(frame);
 
   while (state->stack.Count() > 1 || state->stack.Top()->todo.Count() > 1 ||
diff --git a/executable_semantics/interpreter/typecheck.cpp b/executable_semantics/interpreter/typecheck.cpp
index afede2623823..006dbff5c2ae 100644
--- a/executable_semantics/interpreter/typecheck.cpp
+++ b/executable_semantics/interpreter/typecheck.cpp
@@ -12,6 +12,7 @@
 
 #include "common/ostream.h"
 #include "executable_semantics/ast/function_definition.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/common/error.h"
 #include "executable_semantics/common/tracing_flag.h"
 #include "executable_semantics/interpreter/interpreter.h"
@@ -512,9 +513,10 @@ auto TypeCheckPattern(const Pattern* p, TypeEnv types, Env values,
           FATAL_COMPILATION_ERROR(binding.LineNumber())
               << "Unsupported type pattern";
       }
-      auto new_p = new BindingPattern(
+      auto new_p = global_arena->New<BindingPattern>(
           binding.LineNumber(), binding.Name(),
-          new ExpressionPattern(ReifyType(type, binding.LineNumber())));
+          global_arena->New<ExpressionPattern>(
+              ReifyType(type, binding.LineNumber())));
       if (binding.Name().has_value()) {
         types.Set(*binding.Name(), type);
       }
@@ -553,7 +555,8 @@ auto TypeCheckPattern(const Pattern* p, TypeEnv types, Env values,
             TuplePattern::Field(field.name, field_result.pattern));
         field_types.push_back({.name = field.name, .value = field_result.type});
       }
-      auto new_tuple = new TuplePattern(tuple.LineNumber(), new_fields);
+      auto new_tuple =
+          global_arena->New<TuplePattern>(tuple.LineNumber(), new_fields);
       auto tuple_t = Value::MakeTupleValue(std::move(field_types));
       return {.pattern = new_tuple, .type = tuple_t, .types = new_types};
     }
@@ -578,7 +581,7 @@ auto TypeCheckPattern(const Pattern* p, TypeEnv types, Env values,
       }
       TCPattern arg_results = TypeCheckPattern(alternative.Arguments(), types,
                                                values, parameter_types);
-      return {.pattern = new AlternativePattern(
+      return {.pattern = global_arena->New<AlternativePattern>(
                   alternative.LineNumber(),
                   ReifyType(choice_type, alternative.LineNumber()),
                   alternative.AlternativeName(),
@@ -589,7 +592,7 @@ auto TypeCheckPattern(const Pattern* p, TypeEnv types, Env values,
     case Pattern::Kind::ExpressionPattern: {
       TCExpression result =
           TypeCheckExp(cast<ExpressionPattern>(p)->Expression(), types, values);
-      return {.pattern = new ExpressionPattern(result.exp),
+      return {.pattern = global_arena->New<ExpressionPattern>(result.exp),
               .type = result.type,
               .types = result.types};
     }
@@ -622,7 +625,8 @@ auto TypeCheckStmt(const Statement* s, TypeEnv types, Env values,
       auto res = TypeCheckExp(s->GetMatch().exp, types, values);
       auto res_type = res.type;
       auto new_clauses =
-          new std::list<std::pair<const Pattern*, const Statement*>>();
+          global_arena
+              ->New<std::list<std::pair<const Pattern*, const Statement*>>>();
       for (auto& clause : *s->GetMatch().clauses) {
         new_clauses->push_back(TypecheckCase(
             res_type, clause.first, clause.second, types, values, ret_type));
@@ -748,7 +752,8 @@ auto CheckOrEnsureReturn(const Statement* stmt, bool void_return, int line_num)
   switch (stmt->tag()) {
     case StatementKind::Match: {
       auto new_clauses =
-          new std::list<std::pair<const Pattern*, const Statement*>>();
+          global_arena
+              ->New<std::list<std::pair<const Pattern*, const Statement*>>>();
       for (auto i = stmt->GetMatch().clauses->begin();
            i != stmt->GetMatch().clauses->end(); ++i) {
         auto s = CheckOrEnsureReturn(i->second, void_return, stmt->line_num);
@@ -827,9 +832,10 @@ auto TypeCheckFunDef(const FunctionDefinition* f, TypeEnv types, Env values)
   auto res = TypeCheckStmt(f->body, param_res.types, values, return_type);
   bool void_return = TypeEqual(return_type, Value::MakeUnitTypeVal());
   auto body = CheckOrEnsureReturn(res.stmt, void_return, f->line_num);
-  return new FunctionDefinition(
+  return global_arena->New<FunctionDefinition>(
       f->line_num, f->name, f->deduced_parameters, f->param_pattern,
-      new ExpressionPattern(ReifyType(return_type, f->line_num)), body);
+      global_arena->New<ExpressionPattern>(ReifyType(return_type, f->line_num)),
+      body);
 }
 
 auto TypeOfFunDef(TypeEnv types, Env values, const FunctionDefinition* fun_def)
diff --git a/executable_semantics/interpreter/value.cpp b/executable_semantics/interpreter/value.cpp
index b454d1ecc4d6..86bbc8022235 100644
--- a/executable_semantics/interpreter/value.cpp
+++ b/executable_semantics/interpreter/value.cpp
@@ -7,6 +7,7 @@
 #include <algorithm>
 
 #include "common/check.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/common/error.h"
 #include "llvm/ADT/StringExtras.h"
 
@@ -111,47 +112,47 @@ auto TupleValue::FindField(const std::string& name) const -> const Value* {
 }
 
 auto Value::MakeIntValue(int i) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = IntValue({.value = i});
   return v;
 }
 
 auto Value::MakeBoolValue(bool b) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = BoolValue({.value = b});
   return v;
 }
 
 auto Value::MakeFunctionValue(std::string name, const Value* param,
                               const Statement* body) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value =
       FunctionValue({.name = std::move(name), .param = param, .body = body});
   return v;
 }
 
 auto Value::MakePointerValue(Address addr) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = PointerValue({.value = addr});
   return v;
 }
 
 auto Value::MakeStructValue(const Value* type, const Value* inits)
     -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = StructValue({.type = type, .inits = inits});
   return v;
 }
 
 auto Value::MakeTupleValue(std::vector<TupleElement> elements) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = TupleValue({.elements = std::move(elements)});
   return v;
 }
 
 auto Value::MakeAlternativeValue(std::string alt_name, std::string choice_name,
                                  const Value* argument) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = AlternativeValue({.alt_name = std::move(alt_name),
                                .choice_name = std::move(choice_name),
                                .argument = argument});
@@ -161,7 +162,7 @@ auto Value::MakeAlternativeValue(std::string alt_name, std::string choice_name,
 auto Value::MakeAlternativeConstructorValue(std::string alt_name,
                                             std::string choice_name)
     -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = AlternativeConstructorValue(
       {.alt_name = std::move(alt_name), .choice_name = std::move(choice_name)});
   return v;
@@ -170,45 +171,45 @@ auto Value::MakeAlternativeConstructorValue(std::string alt_name,
 // Return a first-class continuation represented a fragment
 // of the stack.
 auto Value::MakeContinuationValue(std::vector<Frame*> stack) -> Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = ContinuationValue({.stack = std::move(stack)});
   return v;
 }
 
 auto Value::MakeBindingPlaceholderValue(std::optional<std::string> name,
                                         const Value* type) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = BindingPlaceholderValue({.name = std::move(name), .type = type});
   return v;
 }
 
 auto Value::MakeIntType() -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = IntType();
   return v;
 }
 
 auto Value::MakeBoolType() -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = BoolType();
   return v;
 }
 
 auto Value::MakeTypeType() -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = TypeType();
   return v;
 }
 
 // Return a Continuation type.
 auto Value::MakeContinuationType() -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = ContinuationType();
   return v;
 }
 
 auto Value::MakeAutoType() -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = AutoType();
   return v;
 }
@@ -216,21 +217,21 @@ auto Value::MakeAutoType() -> const Value* {
 auto Value::MakeFunctionType(std::vector<GenericBinding> deduced_params,
                              const Value* param, const Value* ret)
     -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = FunctionType(
       {.deduced = std::move(deduced_params), .param = param, .ret = ret});
   return v;
 }
 
 auto Value::MakePointerType(const Value* type) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = PointerType({.type = type});
   return v;
 }
 
 auto Value::MakeStructType(std::string name, VarValues fields,
                            VarValues methods) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = StructType({.name = std::move(name),
                          .fields = std::move(fields),
                          .methods = std::move(methods)});
@@ -238,20 +239,20 @@ auto Value::MakeStructType(std::string name, VarValues fields,
 }
 
 auto Value::MakeUnitTypeVal() -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = TupleValue({.elements = {}});
   return v;
 }
 
 auto Value::MakeChoiceType(std::string name, VarValues alts) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value =
       ChoiceType({.name = std::move(name), .alternatives = std::move(alts)});
   return v;
 }
 
 auto Value::MakeVariableType(std::string name) -> const Value* {
-  auto* v = new Value();
+  auto* v = global_arena->New<Value>();
   v->value = VariableType({.name = std::move(name)});
   return v;
 }
diff --git a/executable_semantics/syntax/BUILD b/executable_semantics/syntax/BUILD
index 62e7fe5109d8..e48972ea286d 100644
--- a/executable_semantics/syntax/BUILD
+++ b/executable_semantics/syntax/BUILD
@@ -33,6 +33,7 @@ cc_library(
         "//common:ostream",
         "//executable_semantics/ast:declaration",
         "//executable_semantics/ast:expression",
+        "//executable_semantics/common:arena",
         "//executable_semantics/common:error",
         "//executable_semantics/common:tracing_flag",
         "//executable_semantics/interpreter",
diff --git a/executable_semantics/syntax/lexer.lpp b/executable_semantics/syntax/lexer.lpp
index 09c651e760a5..10e2894d43b1 100644
--- a/executable_semantics/syntax/lexer.lpp
+++ b/executable_semantics/syntax/lexer.lpp
@@ -178,10 +178,7 @@ operator and its operand, leading to three more cases:
 
 {identifier} {
   BEGIN(AFTER_OPERAND);
-  int n = strlen(yytext);
-  auto r = reinterpret_cast<char*>(malloc((n + 1) * sizeof(char)));
-  strncpy(r, yytext, n + 1);
-  return yy::parser::make_identifier(r, context.current_token_position);
+  return yy::parser::make_identifier(yytext, context.current_token_position);
 }
 
 {integer_literal} {
diff --git a/executable_semantics/syntax/parser.ypp b/executable_semantics/syntax/parser.ypp
index 23482c0ef403..920150c0e89f 100644
--- a/executable_semantics/syntax/parser.ypp
+++ b/executable_semantics/syntax/parser.ypp
@@ -63,6 +63,7 @@
 #include "executable_semantics/ast/expression.h"
 #include "executable_semantics/ast/function_definition.h"
 #include "executable_semantics/ast/pattern.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/syntax/paren_contents.h"
 
 namespace Carbon {
@@ -82,8 +83,8 @@ void yy::parser::error(const location_type&, const std::string& message) {
 }  // %code
 
 %token <int> integer_literal
-%token <char*> identifier
-%type <char*> designator
+%token <std::string> identifier
+%type <std::string> designator
 %type <Carbon::Declaration> declaration
 %type <Carbon::FunctionDefinition> function_declaration
 %type <Carbon::FunctionDefinition> function_definition
@@ -310,17 +311,17 @@ pattern:
   non_expression_pattern
     { $$ = $1; }
 | expression
-    { $$ = new Carbon::ExpressionPattern($1); }
+    { $$ = Carbon::global_arena->New<Carbon::ExpressionPattern>($1); }
 ;
 non_expression_pattern:
   AUTO
-    { $$ = new Carbon::AutoPattern(yylineno); }
+    { $$ = Carbon::global_arena->New<Carbon::AutoPattern>(yylineno); }
 | binding_lhs ":" pattern
-    { $$ = new Carbon::BindingPattern(yylineno, $1, $3); }
+    { $$ = Carbon::global_arena->New<Carbon::BindingPattern>(yylineno, $1, $3); }
 | paren_pattern
     { $$ = $1; }
 | expression tuple_pattern
-    { $$ = new Carbon::AlternativePattern(yylineno, $1, $2); }
+    { $$ = Carbon::global_arena->New<Carbon::AlternativePattern>(yylineno, $1, $2); }
 ;
 binding_lhs:
   identifier { $$ = $1; }
@@ -354,7 +355,7 @@ paren_pattern_contents:
 | paren_pattern_contents "," paren_expression_element
     {
       $$ = $1;
-      $$.elements.push_back({.name = $3.name, .term = new Carbon::ExpressionPattern($3.term)});
+      $$.elements.push_back({.name = $3.name, .term = Carbon::global_arena->New<Carbon::ExpressionPattern>($3.term)});
     }
 | paren_pattern_contents "," paren_pattern_element
     {
@@ -376,24 +377,25 @@ tuple_pattern: paren_pattern_base
 // rules out the possibility of an `expression` at this point.
 maybe_empty_tuple_pattern:
   "(" ")"
-    { $$ = new Carbon::TuplePattern(yylineno, {}); }
+    { $$ = Carbon::global_arena->New<Carbon::TuplePattern>(yylineno, std::vector<Carbon::TuplePattern::Field>()); }
 | tuple_pattern
     { $$ = $1; }
 ;
 clause:
   CASE pattern DBLARROW statement
-    { $$ = new std::pair<const Carbon::Pattern*, const Carbon::Statement*>($2, $4); }
+    { $$ = Carbon::global_arena->New<std::pair<const Carbon::Pattern*, const Carbon::Statement*>>($2, $4); }
 | DEFAULT DBLARROW statement
     {
-      auto vp = new Carbon::BindingPattern(
-          yylineno, std::nullopt, new Carbon::AutoPattern(yylineno));
-      $$ = new std::pair<const Carbon::Pattern*, const Carbon::Statement*>(vp, $3);
+      auto vp = Carbon::global_arena->New<Carbon::BindingPattern>(
+          yylineno, std::nullopt, Carbon::global_arena->New<Carbon::AutoPattern>(yylineno));
+      $$ = Carbon::global_arena->New<std::pair<const Carbon::Pattern*, const Carbon::Statement*>>(vp, $3);
     }
 ;
 clause_list:
   // Empty
     {
-      $$ = new std::list<std::pair<const Carbon::Pattern*, const Carbon::Statement*>>();
+      $$ = Carbon::global_arena->New<std::list<
+          std::pair<const Carbon::Pattern*, const Carbon::Statement*>>>();
     }
 | clause clause_list
     { $$ = $2; $$->push_front(*$1); }
@@ -484,13 +486,13 @@ function_definition:
   FN identifier deduced_params maybe_empty_tuple_pattern return_type block
     {
       $$ = Carbon::FunctionDefinition(
-        yylineno, $2, $3, $4, new Carbon::ExpressionPattern($5), $6);
+        yylineno, $2, $3, $4, Carbon::global_arena->New<Carbon::ExpressionPattern>($5), $6);
     }
 | FN identifier deduced_params maybe_empty_tuple_pattern DBLARROW expression ";"
     {
       $$ = Carbon::FunctionDefinition(
                yylineno, $2, $3, $4,
-               new Carbon::AutoPattern(yylineno),
+               Carbon::global_arena->New<Carbon::AutoPattern>(yylineno),
                Carbon::Statement::MakeReturn(yylineno, $6));
     }
 ;
@@ -498,10 +500,10 @@ function_declaration:
   FN identifier deduced_params maybe_empty_tuple_pattern return_type ";"
     {
       $$ = Carbon::FunctionDefinition(
-        yylineno, $2, $3, $4, new Carbon::ExpressionPattern($5), 0); }
+        yylineno, $2, $3, $4, Carbon::global_arena->New<Carbon::ExpressionPattern>($5), 0); }
 ;
 variable_declaration: identifier ":" pattern
-    { $$ = new Carbon::BindingPattern(yylineno, $1, $3); }
+    { $$ = Carbon::global_arena->New<Carbon::BindingPattern>(yylineno, $1, $3); }
 ;
 member: VAR variable_declaration ";"
     { $$ = Carbon::Member::MakeFieldMember(yylineno, $2); }
diff --git a/executable_semantics/syntax/syntax_helpers.cpp b/executable_semantics/syntax/syntax_helpers.cpp
index 9eb9da1354d9..da8ae39eeba7 100644
--- a/executable_semantics/syntax/syntax_helpers.cpp
+++ b/executable_semantics/syntax/syntax_helpers.cpp
@@ -5,6 +5,7 @@
 #include "executable_semantics/syntax/syntax_helpers.h"
 
 #include "common/ostream.h"
+#include "executable_semantics/common/arena.h"
 #include "executable_semantics/common/tracing_flag.h"
 #include "executable_semantics/interpreter/interpreter.h"
 #include "executable_semantics/interpreter/typecheck.h"
@@ -19,7 +20,7 @@ void ExecProgram(std::list<Declaration>* fs) {
     }
     llvm::outs() << "********** type checking **********\n";
   }
-  state = new State();  // Compile-time state.
+  state = global_arena->New<State>();  // Compile-time state.
   TypeCheckContext p = TopLevel(fs);
   TypeEnv top = p.types;
   Env ct_top = p.values;
diff --git a/executable_semantics/tests.py b/executable_semantics/tests.py
index b56ce5bb511c..bc40b4744d60 100755
--- a/executable_semantics/tests.py
+++ b/executable_semantics/tests.py
@@ -111,9 +111,6 @@ def _update_list(use_git_state):
 
 def _update_golden(test):
     """Updates the golden file for `test` by running executable_semantics."""
-    # TODO(#580): Remove this when leaks are fixed.
-    env = os.environ.copy()
-    env["ASAN_OPTIONS"] = "detect_leaks=0"
     # Invoke the test update directly in order to allow parallel execution
     # (`bazel run` will serialize).
     p = subprocess.run(
@@ -123,7 +120,6 @@ def _update_golden(test):
             "%s/executable_semantics %s/%s.carbon" % (_BINDIR, _TESTDATA, test),
             "--update",
         ],
-        env=env,
         stdout=subprocess.PIPE,
         stderr=subprocess.STDOUT,
     )