diff --git a/src/arch/wasm/CodeGen.zig b/src/arch/wasm/CodeGen.zig
index 14d2cf95c4..af54043f7a 100644
--- a/src/arch/wasm/CodeGen.zig
+++ b/src/arch/wasm/CodeGen.zig
@@ -4160,7 +4160,7 @@ fn airIntcast(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
 
     const op_bits = toWasmBits(@as(u16, @intCast(operand_ty.bitSize(mod)))).?;
     const wanted_bits = toWasmBits(@as(u16, @intCast(ty.bitSize(mod)))).?;
-    const result = if (op_bits == wanted_bits)
+    const result = if (op_bits == wanted_bits and !ty.isSignedInt(mod))
         func.reuseOperand(ty_op.operand, operand)
     else
         try (try func.intcast(operand, operand_ty, ty)).toLocal(func, ty);
@@ -4181,7 +4181,19 @@ fn intcast(func: *CodeGen, operand: WValue, given: Type, wanted: Type) InnerErro
 
     const op_bits = toWasmBits(given_bitsize).?;
     const wanted_bits = toWasmBits(wanted_bitsize).?;
-    if (op_bits == wanted_bits) return operand;
+    if (op_bits == wanted_bits) {
+        if (given.isSignedInt(mod)) {
+            if (given_bitsize < wanted_bitsize) {
+                // signed integers are stored as two's complement,
+                // when we upcast from a smaller integer to larger
+                // integers, we must get its absolute value similar to
+                // i64_extend_i32_s instruction.
+                return func.signAbsValue(operand, given);
+            }
+            return func.wrapOperand(operand, wanted);
+        }
+        return operand;
+    }
 
     if (op_bits > 32 and op_bits <= 64 and wanted_bits == 32) {
         try func.emitWValue(operand);
diff --git a/test/behavior/cast_int.zig b/test/behavior/cast_int.zig
index 6d4f530409..09733d00a0 100644
--- a/test/behavior/cast_int.zig
+++ b/test/behavior/cast_int.zig
@@ -14,3 +14,18 @@ test "@intCast i32 to u7" {
     var z = x >> @as(u7, @intCast(y));
     try expect(z == 0xff);
 }
+
+test "coerce i8 to i32 and @intCast back" {
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
+
+    var x: i8 = -5;
+    var y: i32 = -5;
+    try expect(y == x);
+
+    var x2: i32 = -5;
+    var y2: i8 = -5;
+    try expect(y2 == @as(i8, @intCast(x2)));
+}