fix corner case in `dead_code` (#5031)

fixes #5030

2 files changed, 56 insertions, 4 deletions

diff --git a/test/compress/dead-code.js b/test/compress/dead-code.js
index 4493deb0..ecf5ce4b 100644
--- a/test/compress/dead-code.js
+++ b/test/compress/dead-code.js
@@ -1103,6 +1103,21 @@ last_assign_finally: {
     expect_stdout: "PASS"
 }
 
+consecutive_assignments: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        while (a = void 0, a = "PASS", console.log(a));
+        var a;
+    }
+    expect: {
+        while (void 0, a = "PASS", console.log(a));
+        var a;
+    }
+    expect_stdout: "PASS"
+}
+
 issue_3578: {
     options = {
         dead_code: true,
@@ -1584,3 +1599,37 @@ issue_4570: {
     }
     expect_stdout: "NaN"
 }
+
+issue_5030: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        (function(a, b) {
+            a = function f() {
+                if (a)
+                    if (b--)
+                        setImmediate(f);
+                    else
+                        console.log("FAIL");
+                else
+                    console.log("PASS");
+            }();
+        })(42, 1);
+    }
+    expect: {
+        (function(a, b) {
+            a = function f() {
+                if (a)
+                    if (b--)
+                        setImmediate(f);
+                    else
+                        console.log("FAIL");
+                else
+                    console.log("PASS");
+            }();
+        })(42, 1);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=0.12"
+}
diff --git a/test/compress/default-values.js b/test/compress/default-values.js
index d1637524..6406d4a2 100644
--- a/test/compress/default-values.js
+++ b/test/compress/default-values.js
@@ -422,7 +422,9 @@ inline_loop_1: {
 inline_loop_2: {
     options = {
         inline: true,
+        sequences: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         while (function(a = [ "PASS" ]) {
@@ -432,10 +434,11 @@ inline_loop_2: {
         }());
     }
     expect: {
-        while (a = [ "PASS" ], a = function f(b) {
-            console.log(a[b]);
-        }(0), void 0) ;
-        var a;
+        while (a = [ "PASS" ],
+            b = void 0,
+            b = 0,
+            void (a = void console.log(a[b])));
+        var a, b;
     }
     expect_stdout: "PASS"
     node_version: ">=6"