diff --git a/js/src/jit-test/tests/ion/bug1874502.js b/js/src/jit-test/tests/ion/bug1874502.js
new file mode 100644
index 00000000000..347c5467485
--- /dev/null
+++ b/js/src/jit-test/tests/ion/bug1874502.js
@@ -0,0 +1,8 @@
+// |jit-test| --no-threads; --fast-warmup
+
+function f(x) {
+    Math.fround(function () { x; });
+  }
+  for (let i = 0; i < 30; i++) {
+    f(Math.fround(1));
+  }
\ No newline at end of file
diff --git a/js/src/jit/arm/MacroAssembler-arm.cpp b/js/src/jit/arm/MacroAssembler-arm.cpp
index da358c5ec9d..fe4f36ab26e 100644
--- a/js/src/jit/arm/MacroAssembler-arm.cpp
+++ b/js/src/jit/arm/MacroAssembler-arm.cpp
@@ -4592,7 +4592,7 @@ void MacroAssembler::moveValue(const TypedOrValueRegister& src,
     return;
   }
 
-  ScratchFloat32Scope scratch(*this);
+  ScratchDoubleScope scratch(*this);
   FloatRegister freg = reg.fpu();
   if (type == MIRType::Float32) {
     convertFloat32ToDouble(freg, scratch);