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diff --git a/‎src/compiler/transformers/ts.ts
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+5-3Lines changed: 5 additions & 3 deletions b/‎src/compiler/transformers/ts.ts
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+5-3Lines changed: 5 additions & 3 deletions
diff --git a/‎tests/baselines/reference/declarationEmitAliasExportStar.js
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+11Lines changed: 11 additions & 0 deletions b/‎tests/baselines/reference/declarationEmitAliasExportStar.js
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+11Lines changed: 11 additions & 0 deletions
diff --git a/‎tests/baselines/reference/es6ExportEqualsInterop.js
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+2Lines changed: 2 additions & 0 deletions b/‎tests/baselines/reference/es6ExportEqualsInterop.js
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+2Lines changed: 2 additions & 0 deletions
diff --git a/‎tests/baselines/reference/exportStarForValues.js
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+12-1Lines changed: 12 additions & 1 deletion b/‎tests/baselines/reference/exportStarForValues.js
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+12-1Lines changed: 12 additions & 1 deletion
diff --git a/‎tests/baselines/reference/exportStarForValues10.js
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+4-1Lines changed: 4 additions & 1 deletion b/‎tests/baselines/reference/exportStarForValues10.js
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+4-1Lines changed: 4 additions & 1 deletion
diff --git a/‎tests/baselines/reference/exportStarForValues2.js
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+24-2Lines changed: 24 additions & 2 deletions b/‎tests/baselines/reference/exportStarForValues2.js
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+24-2Lines changed: 24 additions & 2 deletions
diff --git a/‎tests/baselines/reference/exportStarForValues3.js
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+49-4Lines changed: 49 additions & 4 deletions b/‎tests/baselines/reference/exportStarForValues3.js
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+49-4Lines changed: 49 additions & 4 deletions
diff --git a/‎tests/baselines/reference/exportStarForValues4.js
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+25-2Lines changed: 25 additions & 2 deletions b/‎tests/baselines/reference/exportStarForValues4.js
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+25-2Lines changed: 25 additions & 2 deletions
diff --git a/‎tests/baselines/reference/exportStarForValues5.js
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+12-1Lines changed: 12 additions & 1 deletion b/‎tests/baselines/reference/exportStarForValues5.js
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+12-1Lines changed: 12 additions & 1 deletion
diff --git a/‎tests/baselines/reference/exportStarForValues6.js
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+16-2Lines changed: 16 additions & 2 deletions b/‎tests/baselines/reference/exportStarForValues6.js
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+16-2Lines changed: 16 additions & 2 deletions
@@ -2859,9 +2859,11 @@ namespace ts {
                 return undefined;
             }
 
-            if (!node.exportClause) {
-                // Elide a star export if the module it references does not export a value.
-                return compilerOptions.isolatedModules || resolver.moduleExportsSomeValue(node.moduleSpecifier!) ? node : undefined;
+            if (!node.exportClause || isNamespaceExport(node.exportClause)) {
+                // never elide `export <whatever> from <whereever>` declarations -
+                // they should be kept for sideffects/untyped exports, even when the
+                // type checker doesn't know about any exports
+                return node;
             }
 
             if (!resolver.isValueAliasDeclaration(node)) {
 
@@ -14,7 +14,18 @@ export const thing2 = (param: things.ThingB) => null;
 exports.__esModule = true;
 //// [things.js]
 "use strict";
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
 exports.__esModule = true;
+__exportStar(require("./thingB"), exports);
 //// [index.js]
 "use strict";
 exports.__esModule = true;
 
@@ -300,6 +300,8 @@ var class_2 = require("class");
 __createBinding(exports, class_2, "a", "a9");
 var class_module_2 = require("class-module");
 __createBinding(exports, class_module_2, "a", "a0");
+// export-star
+__exportStar(require("interface"), exports);
 __exportStar(require("variable"), exports);
 __exportStar(require("interface-variable"), exports);
 __exportStar(require("module"), exports);
 
@@ -13,8 +13,19 @@ define(["require", "exports"], function (require, exports) {
     exports.__esModule = true;
 });
 //// [file2.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file1"], function (require, exports, file1_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file1_1, exports);
     var x;
 });
@@ -34,7 +34,7 @@ System.register([], function (exports_1, context_1) {
     };
 });
 //// [file2.js]
-System.register(["file0"], function (exports_1, context_1) {
+System.register(["file0", "file1"], function (exports_1, context_1) {
     "use strict";
     var x;
     var __moduleName = context_1 && context_1.id;
@@ -49,6 +49,9 @@ System.register(["file0"], function (exports_1, context_1) {
         setters: [
             function (file0_1_1) {
                 exportStar_1(file0_1_1);
+            },
+            function (file1_1_1) {
+                exportStar_1(file1_1_1);
             }
         ],
         execute: function () {
 
@@ -17,14 +17,36 @@ define(["require", "exports"], function (require, exports) {
     exports.__esModule = true;
 });
 //// [file2.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file1"], function (require, exports, file1_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file1_1, exports);
     var x = 1;
 });
 //// [file3.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file2"], function (require, exports, file2_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file2_1, exports);
     var x = 1;
 });
@@ -29,26 +29,71 @@ define(["require", "exports"], function (require, exports) {
     exports.__esModule = true;
 });
 //// [file2.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file1"], function (require, exports, file1_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file1_1, exports);
     var x = 1;
 });
 //// [file3.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file1"], function (require, exports, file1_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file1_1, exports);
     var x = 1;
 });
 //// [file4.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file2", "file3"], function (require, exports, file2_1, file3_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file2_1, exports);
+    __exportStar(file3_1, exports);
     var x = 1;
 });
 //// [file5.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file4"], function (require, exports, file4_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file4_1, exports);
     var x = 1;
 });
@@ -21,14 +21,37 @@ define(["require", "exports"], function (require, exports) {
     exports.__esModule = true;
 });
 //// [file3.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file2"], function (require, exports, file2_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file2_1, exports);
     var x = 1;
 });
 //// [file2.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file1", "file3"], function (require, exports, file1_1, file3_1) {
     "use strict";
     exports.__esModule = true;
+    __exportStar(file1_1, exports);
+    __exportStar(file3_1, exports);
     var x = 1;
 });
@@ -13,8 +13,19 @@ define(["require", "exports"], function (require, exports) {
     exports.__esModule = true;
 });
 //// [file2.js]
-define(["require", "exports"], function (require, exports) {
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __exportStar = (this && this.__exportStar) || function(m, exports) {
+    for (var p in m) if (!exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+}
+define(["require", "exports", "file1"], function (require, exports, file1_1) {
     "use strict";
     exports.__esModule = true;
     exports.x = void 0;
+    __exportStar(file1_1, exports);
 });
@@ -18,12 +18,26 @@ System.register([], function (exports_1, context_1) {
     };
 });
 //// [file2.js]
-System.register([], function (exports_1, context_1) {
+System.register(["file1"], function (exports_1, context_1) {
     "use strict";
     var x;
     var __moduleName = context_1 && context_1.id;
+    var exportedNames_1 = {
+        "x": true
+    };
+    function exportStar_1(m) {
+        var exports = {};
+        for (var n in m) {
+            if (n !== "default" && !exportedNames_1.hasOwnProperty(n)) exports[n] = m[n];
+        }
+        exports_1(exports);
+    }
     return {
-        setters: [],
+        setters: [
+            function (file1_1_1) {
+                exportStar_1(file1_1_1);
+            }
+        ],
         execute: function () {
             exports_1("x", x = 1);
         }
Original file line number	Diff line number	Diff line change
`@@ -2859,9 +2859,11 @@ namespace ts {`
`2859`	`2859`	`return undefined;`
`2860`	`2860`	`}`
`2861`	`2861`
`2862`		`- if (!node.exportClause) {`
`2863`		`- // Elide a star export if the module it references does not export a value.`
`2864`		`- return compilerOptions.isolatedModules \|\| resolver.moduleExportsSomeValue(node.moduleSpecifier!) ? node : undefined;`
	`2862`	`+ if (!node.exportClause \|\| isNamespaceExport(node.exportClause)) {`
	`2863`	+ // never elide `export <whatever> from <whereever>` declarations -
	`2864`	`+ // they should be kept for sideffects/untyped exports, even when the`
	`2865`	`+ // type checker doesn't know about any exports`
	`2866`	`+ return node;`
`2865`	`2867`	`}`
`2866`	`2868`
`2867`	`2869`	`if (!resolver.isValueAliasDeclaration(node)) {`