diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index c871f2d765bea5eac10790eebb9c4cff53276832..3804e2ba4f42be8f36c9d052983cfd9261d2e8ea 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -6875,6 +6875,7 @@ fn airReduce(f: *Function, inst: Air.Inst.Index) !CValue {
         },
         .big => .{ false, true },
     } else .{ false, false };
+    const operator_wraps = use_operator and scalar_ty.intInfo(zcu).bits == 8 * scalar_ty.abiSize(zcu);
     const op: union(enum) {
         const Func = struct { operation: []const u8, info: BuiltinInfo = .none };
         builtin: Func,
@@ -6895,12 +6896,12 @@ fn airReduce(f: *Function, inst: Air.Inst.Index) !CValue {
             else => unreachable,
         },
         .Add => switch (scalar_ty.zigTypeTag(zcu)) {
-            .int => if (use_operator) .{ .infix = " += " } else .{ .builtin = .{ .operation = "addw", .info = .bits } },
+            .int => if (operator_wraps) .{ .infix = " += " } else .{ .builtin = .{ .operation = "addw", .info = .bits } },
             .float => .{ .builtin = .{ .operation = "add" } },
             else => unreachable,
         },
         .Mul => switch (scalar_ty.zigTypeTag(zcu)) {
-            .int => if (use_operator) .{ .infix = " *= " } else .{ .builtin = .{ .operation = "mulw", .info = .bits } },
+            .int => if (operator_wraps) .{ .infix = " *= " } else .{ .builtin = .{ .operation = "mulw", .info = .bits } },
             .float => .{ .builtin = .{ .operation = "mul" } },
             else => unreachable,
         },
diff --git a/test/behavior/vector.zig b/test/behavior/vector.zig
index 02e674ecb4c748faacf31c7609c1ea507a2c6ffc..1c15acb053da4d17c052f31a1caed509dd24d5c4 100644
--- a/test/behavior/vector.zig
+++ b/test/behavior/vector.zig
@@ -969,6 +969,7 @@ test "vector reduce operation" {
             try testReduce(.Add, [4]u64{ 9, 99, 999, 9999 }, @as(u64, 11106));
             try testReduce(.Add, [4]i128{ -9, -99, -999, -9999 }, @as(i128, -11106));
             try testReduce(.Add, [4]u128{ 9, 99, 999, 9999 }, @as(u128, 11106));
+            try testReduce(.Add, [4]u7{ 100, 100, 0, 0 }, @as(u7, 72));
             try testReduce(.Add, [4]f16{ -1.9, 5.1, -60.3, 100.0 }, @as(f16, 42.9));
             try testReduce(.Add, [4]f32{ -1.9, 5.1, -60.3, 100.0 }, @as(f32, 42.9));
             try testReduce(.Add, [4]f64{ -1.9, 5.1, -60.3, 100.0 }, @as(f64, 42.9));
@@ -1017,6 +1018,7 @@ test "vector reduce operation" {
             try testReduce(.Mul, [4]u64{ 9, 99, 999, 9999 }, @as(u64, 8900199891));
             try testReduce(.Mul, [4]i128{ -9, -99, -999, 9999 }, @as(i128, -8900199891));
             try testReduce(.Mul, [4]u128{ 9, 99, 999, 9999 }, @as(u128, 8900199891));
+            try testReduce(.Mul, [4]i3{ 3, 2, 1, 1 }, @as(i3, -2));
             try testReduce(.Mul, [4]f16{ -1.9, 5.1, -60.3, 100.0 }, @as(f16, 58430.7));
             try testReduce(.Mul, [4]f32{ -1.9, 5.1, -60.3, 100.0 }, @as(f32, 58430.7));
             try testReduce(.Mul, [4]f64{ -1.9, 5.1, -60.3, 100.0 }, @as(f64, 58430.7));