diff --git a/src/cmd/link/internal/wasm/asm.go b/src/cmd/link/internal/wasm/asm.go
index ee0a5176ac..bf22c28311 100644
--- a/src/cmd/link/internal/wasm/asm.go
+++ b/src/cmd/link/internal/wasm/asm.go
@@ -296,10 +296,11 @@ func writeTableSec(ctxt *ld.Link, fns []*wasmFunc) {
 func writeMemorySec(ctxt *ld.Link) {
 	sizeOffset := writeSecHeader(ctxt, sectionMemory)
 
-	const (
-		initialSize  = 16 << 20 // 16MB, enough for runtime init without growing
-		wasmPageSize = 64 << 10 // 64KB
-	)
+	dataSection := ctxt.Syms.Lookup("runtime.data", 0).Sect
+	dataEnd := dataSection.Vaddr + dataSection.Length
+	var initialSize = dataEnd + 16<<20 // 16MB, enough for runtime init without growing
+
+	const wasmPageSize = 64 << 10 // 64KB
 
 	writeUleb128(ctxt.Out, 1)                        // number of memories
 	ctxt.Out.WriteByte(0x00)                         // no maximum memory size
diff --git a/test/fixedbugs/issue34395.go b/test/fixedbugs/issue34395.go
new file mode 100644
index 0000000000..eb5a8558e1
--- /dev/null
+++ b/test/fixedbugs/issue34395.go
@@ -0,0 +1,17 @@
+// run
+
+// Copyright 2019 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that a binary with a large data section can load. This failed on wasm.
+
+package main
+
+var test = [100 * 1024 * 1024]byte{42}
+
+func main() {
+	if test[0] != 42 {
+		panic("bad")
+	}
+}