diff --git a/lib/std/io/c_writer.zig b/lib/std/io/c_writer.zig
index d962bfd854..80dcba3f6f 100644
--- a/lib/std/io/c_writer.zig
+++ b/lib/std/io/c_writer.zig
@@ -30,7 +30,7 @@ fn cWriterWrite(c_file: *std.c.FILE, bytes: []const u8) std.fs.File.WriteError!u
     }
 }
 
-test {
+test "C Writer" {
     if (!builtin.link_libc or builtin.os.tag == .wasi) return error.SkipZigTest;
 
     const filename = "tmp_io_test_file.txt";
diff --git a/lib/std/mem.zig b/lib/std/mem.zig
index 13322c9bee..b0338bdf20 100644
--- a/lib/std/mem.zig
+++ b/lib/std/mem.zig
@@ -2831,6 +2831,8 @@ pub fn asBytes(ptr: anytype) AsBytesReturnType(@TypeOf(ptr)) {
 }
 
 test "asBytes" {
+    if (builtin.zig_backend == .stage1) return error.SkipZigTest;
+
     const deadbeef = @as(u32, 0xDEADBEEF);
     const deadbeef_bytes = switch (native_endian) {
         .Big => "\xDE\xAD\xBE\xEF",
@@ -2857,7 +2859,14 @@ test "asBytes" {
         .c = 0xDE,
         .d = 0xA1,
     };
-    try testing.expect(eql(u8, asBytes(&inst), "\xBE\xEF\xDE\xA1"));
+    switch (native_endian) {
+        .Little => {
+            try testing.expect(eql(u8, asBytes(&inst), "\xBE\xEF\xDE\xA1"));
+        },
+        .Big => {
+            try testing.expect(eql(u8, asBytes(&inst), "\xA1\xDE\xEF\xBE"));
+        },
+    }
 
     const ZST = struct {};
     const zero = ZST{};
@@ -2917,6 +2926,8 @@ pub fn bytesAsValue(comptime T: type, bytes: anytype) BytesAsValueReturnType(T,
 }
 
 test "bytesAsValue" {
+    if (builtin.zig_backend == .stage1) return error.SkipZigTest;
+
     const deadbeef = @as(u32, 0xDEADBEEF);
     const deadbeef_bytes = switch (native_endian) {
         .Big => "\xDE\xAD\xBE\xEF",
@@ -2948,7 +2959,10 @@ test "bytesAsValue" {
         .c = 0xDE,
         .d = 0xA1,
     };
-    const inst_bytes = "\xBE\xEF\xDE\xA1";
+    const inst_bytes = switch (native_endian) {
+        .Little => "\xBE\xEF\xDE\xA1",
+        .Big => "\xA1\xDE\xEF\xBE",
+    };
     const inst2 = bytesAsValue(S, inst_bytes);
     try testing.expect(meta.eql(inst, inst2.*));
 }
@@ -3115,6 +3129,8 @@ test "sliceAsBytes with sentinel slice" {
 }
 
 test "sliceAsBytes packed struct at runtime and comptime" {
+    if (builtin.zig_backend == .stage1) return error.SkipZigTest;
+
     const Foo = packed struct {
         a: u4,
         b: u4,
@@ -3124,16 +3140,8 @@ test "sliceAsBytes packed struct at runtime and comptime" {
             var foo: Foo = undefined;
             var slice = sliceAsBytes(@as(*[1]Foo, &foo)[0..1]);
             slice[0] = 0x13;
-            switch (native_endian) {
-                .Big => {
-                    try testing.expect(foo.a == 0x1);
-                    try testing.expect(foo.b == 0x3);
-                },
-                .Little => {
-                    try testing.expect(foo.a == 0x3);
-                    try testing.expect(foo.b == 0x1);
-                },
-            }
+            try testing.expect(foo.a == 0x3);
+            try testing.expect(foo.b == 0x1);
         }
     };
     try S.doTheTest();
diff --git a/lib/std/x/net/bpf.zig b/lib/std/x/net/bpf.zig
index e0204b3bc5..e8db9a3e0e 100644
--- a/lib/std/x/net/bpf.zig
+++ b/lib/std/x/net/bpf.zig
@@ -706,12 +706,8 @@ fn expectFail(expected_error: anyerror, data: anytype, filter: []Insn) !void {
 }
 
 test "simulator coverage" {
-    const some_data: packed struct {
-        foo: u32,
-        bar: u8,
-    } = .{
-        .foo = mem.nativeToBig(u32, 0xaabbccdd),
-        .bar = 0x7f,
+    const some_data = [_]u8{
+        0xaa, 0xbb, 0xcc, 0xdd, 0x7f,
     };
 
     try expectPass(&some_data, &.{
@@ -764,7 +760,7 @@ test "simulator coverage" {
         // ld #len
         // fail if A != 5
         Insn.ld_len(),
-        Insn.jmp(.jeq, .{ .k = @sizeOf(@TypeOf(some_data)) }, 1, 0),
+        Insn.jmp(.jeq, .{ .k = some_data.len }, 1, 0),
         Insn.ret(.{ .k = 9 }),
         // ld #0
         // ld arc4random()
diff --git a/src/Sema.zig b/src/Sema.zig
index f7d8aef12d..550f51d7c5 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -7096,6 +7096,7 @@ fn funcCommon(
         if (param.ty.tag() == .generic_poison) is_generic = true;
     }
 
+    var destroy_fn_on_error = false;
     const new_func: *Module.Fn = new_func: {
         if (!has_body) break :new_func undefined;
         if (sema.comptime_args_fn_inst == func_inst) {
@@ -7103,9 +7104,10 @@ fn funcCommon(
             sema.preallocated_new_func = null; // take ownership
             break :new_func new_func;
         }
+        destroy_fn_on_error = true;
         break :new_func try sema.gpa.create(Module.Fn);
     };
-    errdefer if (has_body) sema.gpa.destroy(new_func);
+    errdefer if (destroy_fn_on_error) sema.gpa.destroy(new_func);
 
     var maybe_inferred_error_set_node: ?*Module.Fn.InferredErrorSetListNode = null;
     errdefer if (maybe_inferred_error_set_node) |node| sema.gpa.destroy(node);
diff --git a/src/codegen/llvm.zig b/src/codegen/llvm.zig
index 4275a1b69d..8857c96bc1 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -5244,7 +5244,7 @@ pub const FuncGen = struct {
         const operand_ty = self.air.typeOf(pl_op.operand);
         const name = self.air.nullTerminatedString(pl_op.payload);
 
-        if (needDbgVarWorkaround(self.dg, operand_ty)) {
+        if (needDbgVarWorkaround(self.dg)) {
             return null;
         }
 
@@ -5432,6 +5432,25 @@ pub const FuncGen = struct {
                 total_i += 1;
             }
         }
+
+        // For some targets, Clang unconditionally adds some clobbers to all inline assembly.
+        // While this is probably not strictly necessary, if we don't follow Clang's lead
+        // here then we may risk tripping LLVM bugs since anything not used by Clang tends
+        // to be buggy and regress often.
+        switch (target.cpu.arch) {
+            .x86_64, .i386 => {
+                if (total_i != 0) try llvm_constraints.append(self.gpa, ',');
+                try llvm_constraints.appendSlice(self.gpa, "~{dirflag},~{fpsr},~{flags}");
+                total_i += 3;
+            },
+            .mips, .mipsel, .mips64, .mips64el => {
+                if (total_i != 0) try llvm_constraints.append(self.gpa, ',');
+                try llvm_constraints.appendSlice(self.gpa, "~{$1}");
+                total_i += 1;
+            },
+            else => {},
+        }
+
         const asm_source = std.mem.sliceAsBytes(self.air.extra[extra_i..])[0..extra.data.source_len];
 
         // hackety hacks until stage2 has proper inline asm in the frontend.
@@ -6988,7 +7007,7 @@ pub const FuncGen = struct {
 
         const inst_ty = self.air.typeOfIndex(inst);
         if (self.dg.object.di_builder) |dib| {
-            if (needDbgVarWorkaround(self.dg, inst_ty)) {
+            if (needDbgVarWorkaround(self.dg)) {
                 return arg_val;
             }
 
@@ -9255,13 +9274,11 @@ const AnnotatedDITypePtr = enum(usize) {
 const lt_errors_fn_name = "__zig_lt_errors_len";
 
 /// Without this workaround, LLVM crashes with "unknown codeview register H1"
-/// TODO use llvm-reduce and file upstream LLVM bug for this.
-fn needDbgVarWorkaround(dg: *DeclGen, ty: Type) bool {
-    if (ty.tag() == .f16) {
-        const target = dg.module.getTarget();
-        if (target.os.tag == .windows and target.cpu.arch == .aarch64) {
-            return true;
-        }
+/// https://github.com/llvm/llvm-project/issues/56484
+fn needDbgVarWorkaround(dg: *DeclGen) bool {
+    const target = dg.module.getTarget();
+    if (target.os.tag == .windows and target.cpu.arch == .aarch64) {
+        return true;
     }
     return false;
 }
diff --git a/src/zig_llvm.cpp b/src/zig_llvm.cpp
index abb1eb0a99..52c202fded 100644
--- a/src/zig_llvm.cpp
+++ b/src/zig_llvm.cpp
@@ -1134,6 +1134,7 @@ void ZigLLVMAddModuleDebugInfoFlag(LLVMModuleRef module) {
 }
 
 void ZigLLVMAddModuleCodeViewFlag(LLVMModuleRef module) {
+    unwrap(module)->addModuleFlag(Module::Warning, "Debug Info Version", DEBUG_METADATA_VERSION);
     unwrap(module)->addModuleFlag(Module::Warning, "CodeView", 1);
 }