diff --git a/lib/std/special/compiler_rt.zig b/lib/std/special/compiler_rt.zig
index f5e83b5278..8d49fdbd2a 100644
--- a/lib/std/special/compiler_rt.zig
+++ b/lib/std/special/compiler_rt.zig
@@ -149,7 +149,7 @@ comptime {
 
     @export(@import("compiler_rt/clzsi2.zig").__clzsi2, .{ .name = "__clzsi2", .linkage = linkage });
 
-    if (builtin.arch.isARM() and !is_test) {
+    if ((builtin.arch.isARM() or builtin.arch.isThumb()) and !is_test) {
         @export(@import("compiler_rt/arm.zig").__aeabi_unwind_cpp_pr0, .{ .name = "__aeabi_unwind_cpp_pr0", .linkage = linkage });
         @export(@import("compiler_rt/arm.zig").__aeabi_unwind_cpp_pr1, .{ .name = "__aeabi_unwind_cpp_pr1", .linkage = linkage });
         @export(@import("compiler_rt/arm.zig").__aeabi_unwind_cpp_pr2, .{ .name = "__aeabi_unwind_cpp_pr2", .linkage = linkage });
diff --git a/lib/std/target/riscv.zig b/lib/std/target/riscv.zig
index 315329306e..ddf1049a20 100644
--- a/lib/std/target/riscv.zig
+++ b/lib/std/target/riscv.zig
@@ -78,7 +78,6 @@ pub const cpu = struct {
             .d,
             .f,
             .m,
-            .relax,
         }),
     };
 
@@ -92,7 +91,6 @@ pub const cpu = struct {
             .d,
             .f,
             .m,
-            .relax,
         }),
     };
 
diff --git a/src/ir.cpp b/src/ir.cpp
index 7f2348caf2..3fc2ddadeb 100644
--- a/src/ir.cpp
+++ b/src/ir.cpp
@@ -11873,10 +11873,15 @@ static ConstCastOnly types_match_const_cast_only(IrAnalyze *ira, ZigType *wanted
     }
 
     if (wanted_type->id == ZigTypeIdInt && actual_type->id == ZigTypeIdInt) {
-        result.id = ConstCastResultIdIntShorten;
-        result.data.int_shorten = heap::c_allocator.allocate_nonzero<ConstCastIntShorten>(1);
-        result.data.int_shorten->wanted_type = wanted_type;
-        result.data.int_shorten->actual_type = actual_type;
+        if (wanted_type->data.integral.is_signed != actual_type->data.integral.is_signed ||
+            wanted_type->data.integral.bit_count != actual_type->data.integral.bit_count)
+        {
+            result.id = ConstCastResultIdIntShorten;
+            result.data.int_shorten = heap::c_allocator.allocate_nonzero<ConstCastIntShorten>(1);
+            result.data.int_shorten->wanted_type = wanted_type;
+            result.data.int_shorten->actual_type = actual_type;
+            return result;
+        }
         return result;
     }
 
diff --git a/test/stage1/behavior/atomics.zig b/test/stage1/behavior/atomics.zig
index 7155e80094..0347f6f94a 100644
--- a/test/stage1/behavior/atomics.zig
+++ b/test/stage1/behavior/atomics.zig
@@ -146,8 +146,8 @@ fn testAtomicStore() void {
 }
 
 test "atomicrmw with floats" {
-    if (builtin.arch == .aarch64 or builtin.arch == .arm)
-        return;
+    if (builtin.arch == .aarch64 or builtin.arch == .arm or builtin.arch == .riscv64)
+        return error.SkipZigTest;
     testAtomicRmwFloat();
 }
 
diff --git a/test/stage1/behavior/cast.zig b/test/stage1/behavior/cast.zig
index a70467e199..f393bfebb5 100644
--- a/test/stage1/behavior/cast.zig
+++ b/test/stage1/behavior/cast.zig
@@ -782,3 +782,16 @@ test "cast between [*c]T and ?[*:0]T on fn parameter" {
     };
     S.doTheTest();
 }
+
+test "cast between C pointer with different but compatible types" {
+    const S = struct {
+        fn foo(arg: [*]c_ushort) u16 {
+            return arg[0];
+        }
+        fn doTheTest() void {
+            var x = [_]u16{ 4, 2, 1, 3 };
+            expect(foo(@ptrCast([*]u16, &x)) == 4);
+        }
+    };
+    S.doTheTest();
+}