diff --git a/src/cmd/compile/internal/gc/pgen.go b/src/cmd/compile/internal/gc/pgen.go
index bdc66f3e27..63e5860950 100644
--- a/src/cmd/compile/internal/gc/pgen.go
+++ b/src/cmd/compile/internal/gc/pgen.go
@@ -153,6 +153,7 @@ func (s *ssafn) AllocFrame(f *ssa.Func) {
 	sort.Sort(byStackVar(fn.Dcl))
 
 	// Reassign stack offsets of the locals that are used.
+	lastHasPtr := false
 	for i, n := range fn.Dcl {
 		if n.Op != ONAME || n.Class() != PAUTO {
 			continue
@@ -167,10 +168,20 @@ func (s *ssafn) AllocFrame(f *ssa.Func) {
 		if w >= thearch.MAXWIDTH || w < 0 {
 			Fatalf("bad width")
 		}
+		if w == 0 && lastHasPtr {
+			// Pad between a pointer-containing object and a zero-sized object.
+			// This prevents a pointer to the zero-sized object from being interpreted
+			// as a pointer to the pointer-containing object (and causing it
+			// to be scanned when it shouldn't be). See issue 24993.
+			w = 1
+		}
 		s.stksize += w
 		s.stksize = Rnd(s.stksize, int64(n.Type.Align))
 		if types.Haspointers(n.Type) {
 			s.stkptrsize = s.stksize
+			lastHasPtr = true
+		} else {
+			lastHasPtr = false
 		}
 		if thearch.LinkArch.InFamily(sys.MIPS, sys.MIPS64, sys.ARM, sys.ARM64, sys.PPC64, sys.S390X) {
 			s.stksize = Rnd(s.stksize, int64(Widthptr))
diff --git a/test/codegen/zerosize.go b/test/codegen/zerosize.go
new file mode 100644
index 0000000000..cd0c83b6ef
--- /dev/null
+++ b/test/codegen/zerosize.go
@@ -0,0 +1,25 @@
+// asmcheck
+
+// Copyright 2018 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.
+
+// Make sure a pointer variable and a zero-sized variable
+// aren't allocated to the same stack slot.
+// See issue 24993.
+
+package codegen
+
+func zeroSize() {
+	c := make(chan struct{})
+	// amd64:`MOVQ\t\$0, ""\.s\+32\(SP\)`
+	var s *int
+	g(&s) // force s to be a stack object
+
+	// amd64:`LEAQ\t""\..*\+31\(SP\)`
+	c <- struct{}{}
+}
+
+//go:noinline
+func g(p **int) {
+}