diff --git a/compiler/symbol.go b/compiler/symbol.go
index 03db781e..c4ce6f21 100644
--- a/compiler/symbol.go
+++ b/compiler/symbol.go
@@ -163,18 +163,20 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 	// External/exported functions may not retain pointer values.
 	// https://golang.org/cmd/cgo/#hdr-Passing_pointers
 	if info.exported {
-		// Set the wasm-import-module attribute if the function's module is set.
-		if info.module != "" {
-
+		if c.archFamily() == "wasm32" {
 			// We need to add the wasm-import-module and the wasm-import-name
-			wasmImportModuleAttr := c.ctx.CreateStringAttribute("wasm-import-module", info.module)
-			llvmFn.AddFunctionAttr(wasmImportModuleAttr)
-
-			// Add the Wasm Import Name, if we are a named wasm import
-			if info.importName != "" {
-				wasmImportNameAttr := c.ctx.CreateStringAttribute("wasm-import-name", info.importName)
-				llvmFn.AddFunctionAttr(wasmImportNameAttr)
+			// attributes.
+			module := info.module
+			if module == "" {
+				module = "env"
 			}
+			llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("wasm-import-module", module))
+
+			name := info.importName
+			if name == "" {
+				name = info.linkName
+			}
+			llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("wasm-import-name", name))
 		}
 		nocaptureKind := llvm.AttributeKindID("nocapture")
 		nocapture := c.ctx.CreateEnumAttribute(nocaptureKind, 0)
diff --git a/compiler/testdata/pragma.ll b/compiler/testdata/pragma.ll
index 9aa1de3d..b243602d 100644
--- a/compiler/testdata/pragma.ll
+++ b/compiler/testdata/pragma.ll
@@ -62,7 +62,7 @@ declare void @main.undefinedFunctionNotInSection(i8*) #0
 
 attributes #0 = { "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" }
 attributes #1 = { nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="extern_func" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="extern_func" "wasm-import-module"="env" "wasm-import-name"="extern_func" }
 attributes #3 = { inlinehint nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" }
 attributes #4 = { noinline nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" }
-attributes #5 = { nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="exportedFunctionInSection" }
+attributes #5 = { nounwind "target-features"="+bulk-memory,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="exportedFunctionInSection" "wasm-import-module"="env" "wasm-import-name"="exportedFunctionInSection" }
diff --git a/src/internal/task/task_asyncify_wasm.S b/src/internal/task/task_asyncify_wasm.S
index 3b00ede1..9aafc110 100644
--- a/src/internal/task/task_asyncify_wasm.S
+++ b/src/internal/task/task_asyncify_wasm.S
@@ -2,12 +2,16 @@
 
 .functype start_unwind (i32) -> ()
 .import_module start_unwind, asyncify
+.import_name start_unwind, start_unwind
 .functype stop_unwind () -> ()
 .import_module stop_unwind, asyncify
+.import_name stop_unwind, stop_unwind
 .functype start_rewind (i32) -> ()
 .import_module start_rewind, asyncify
+.import_name start_rewind, start_rewind
 .functype stop_rewind () -> ()
 .import_module stop_rewind, asyncify
+.import_name stop_rewind, stop_rewind
 
 .global  tinygo_unwind
 .hidden  tinygo_unwind
diff --git a/targets/wasi.json b/targets/wasi.json
index dfec729e..e710b4bb 100644
--- a/targets/wasi.json
+++ b/targets/wasi.json
@@ -15,7 +15,6 @@
 		"-msign-ext"
 	],
 	"ldflags": [
-		"--allow-undefined",
 		"--stack-first",
 		"--no-demangle"
 	],
diff --git a/targets/wasm-undefined.txt b/targets/wasm-undefined.txt
new file mode 100644
index 00000000..ccb6c13c
--- /dev/null
+++ b/targets/wasm-undefined.txt
@@ -0,0 +1,16 @@
+syscall/js.copyBytesToGo
+syscall/js.copyBytesToJS
+syscall/js.finalizeRef
+syscall/js.stringVal
+syscall/js.valueCall
+syscall/js.valueDelete
+syscall/js.valueGet
+syscall/js.valueIndex
+syscall/js.valueInstanceOf
+syscall/js.valueInvoke
+syscall/js.valueLength
+syscall/js.valueLoadString
+syscall/js.valueNew
+syscall/js.valuePrepareString
+syscall/js.valueSet
+syscall/js.valueSetIndex
diff --git a/targets/wasm.json b/targets/wasm.json
index c668a68c..2bcada5f 100644
--- a/targets/wasm.json
+++ b/targets/wasm.json
@@ -15,7 +15,7 @@
 		"-msign-ext"
 	],
 	"ldflags": [
-		"--allow-undefined",
+		"--allow-undefined-file={root}/targets/wasm-undefined.txt",
 		"--stack-first",
 		"--no-demangle"
 	],