std: avoid field/decl name conflicts

Most of these changes seem like improvements. The PDB thing had a TODO
saying it used to crash; I anticipate it works now, we'll see what CI
does.

The `std.os.uefi` field renames are a notable breaking change.

lib/std/crypto/poly1305.zig

@@ -12,7 +12,7 @@ pub const Poly1305 = struct {
     // accumulated hash
     h: [3]u64 = [_]u64{ 0, 0, 0 },
     // random number added at the end (from the secret key)
-    pad: [2]u64,
+    end_pad: [2]u64,
     // how many bytes are waiting to be processed in a partial block
     leftover: usize = 0,
     // partial block buffer
@@ -24,7 +24,7 @@ pub const Poly1305 = struct {
                 mem.readInt(u64, key[0..8], .little) & 0x0ffffffc0fffffff,
                 mem.readInt(u64, key[8..16], .little) & 0x0ffffffc0ffffffc,
             },
-            .pad = [_]u64{
+            .end_pad = [_]u64{
                 mem.readInt(u64, key[16..24], .little),
                 mem.readInt(u64, key[24..32], .little),
             },
@@ -177,9 +177,9 @@ pub const Poly1305 = struct {
         h1 ^= mask & (h1 ^ h_p1);
 
         // Add the first half of the key, we intentionally don't use @addWithOverflow() here.
-        st.h[0] = h0 +% st.pad[0];
-        const c = ((h0 & st.pad[0]) | ((h0 | st.pad[0]) & ~st.h[0])) >> 63;
-        st.h[1] = h1 +% st.pad[1] +% c;
+        st.h[0] = h0 +% st.end_pad[0];
+        const c = ((h0 & st.end_pad[0]) | ((h0 | st.end_pad[0]) & ~st.h[0])) >> 63;
+        st.h[1] = h1 +% st.end_pad[1] +% c;
 
         mem.writeInt(u64, out[0..8], st.h[0], .little);
         mem.writeInt(u64, out[8..16], st.h[1], .little);

lib/std/debug/Pdb.zig

@@ -300,11 +300,10 @@ pub fn getLineNumberInfo(self: *Pdb, module: *Module, address: u64) !std.debug.S
 
                             const found_line_index = start_line_index + line_entry_idx * @sizeOf(pdb.LineNumberEntry);
                             const line_num_entry: *align(1) pdb.LineNumberEntry = @ptrCast(&subsect_info[found_line_index]);
-                            const flags: *align(1) pdb.LineNumberEntry.Flags = @ptrCast(&line_num_entry.Flags);
 
                             return .{
                                 .file_name = source_file_name,
-                                .line = flags.Start,
+                                .line = line_num_entry.Flags.Start,
                                 .column = column,
                             };
                         }

lib/std/enums.zig

@@ -1501,7 +1501,7 @@ test values {
         X,
         Y,
         Z,
-        pub const X = 1;
+        const A = 1;
     };
     try testing.expectEqualSlices(E, &.{ .X, .Y, .Z }, values(E));
 }

lib/std/heap/sbrk_allocator.zig

@@ -7,7 +7,7 @@ const assert = std.debug.assert;
 
 pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
     return struct {
-        pub const vtable = Allocator.VTable{
+        pub const vtable: Allocator.VTable = .{
             .alloc = alloc,
             .resize = resize,
             .free = free,
@@ -15,8 +15,6 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
 
         pub const Error = Allocator.Error;
 
-        lock: std.Thread.Mutex = .{},
-
         const max_usize = math.maxInt(usize);
         const ushift = math.Log2Int(usize);
         const bigpage_size = 64 * 1024;

lib/std/meta.zig

@@ -294,7 +294,7 @@ test declarations {
         pub fn a() void {}
     };
     const U1 = union {
-        a: u8,
+        b: u8,
 
         pub fn a() void {}
     };
@@ -334,7 +334,7 @@ test declarationInfo {
         pub fn a() void {}
     };
     const U1 = union {
-        a: u8,
+        b: u8,
 
         pub fn a() void {}
     };

lib/std/os/uefi/device_path.zig

@@ -4,38 +4,38 @@ const uefi = std.os.uefi;
 const Guid = uefi.Guid;
 
 pub const DevicePath = union(Type) {
-    Hardware: Hardware,
-    Acpi: Acpi,
-    Messaging: Messaging,
-    Media: Media,
-    BiosBootSpecification: BiosBootSpecification,
-    End: End,
+    hardware: Hardware,
+    acpi: Acpi,
+    messaging: Messaging,
+    media: Media,
+    bios_boot_specification: BiosBootSpecification,
+    end: End,
 
     pub const Type = enum(u8) {
-        Hardware = 0x01,
-        Acpi = 0x02,
-        Messaging = 0x03,
-        Media = 0x04,
-        BiosBootSpecification = 0x05,
-        End = 0x7f,
+        hardware = 0x01,
+        acpi = 0x02,
+        messaging = 0x03,
+        media = 0x04,
+        bios_boot_specification = 0x05,
+        end = 0x7f,
         _,
     };
 
     pub const Hardware = union(Subtype) {
-        Pci: *const PciDevicePath,
-        PcCard: *const PcCardDevicePath,
-        MemoryMapped: *const MemoryMappedDevicePath,
-        Vendor: *const VendorDevicePath,
-        Controller: *const ControllerDevicePath,
-        Bmc: *const BmcDevicePath,
+        pci: *const PciDevicePath,
+        pc_card: *const PcCardDevicePath,
+        memory_mapped: *const MemoryMappedDevicePath,
+        vendor: *const VendorDevicePath,
+        controller: *const ControllerDevicePath,
+        bmc: *const BmcDevicePath,
 
         pub const Subtype = enum(u8) {
-            Pci = 1,
-            PcCard = 2,
-            MemoryMapped = 3,
-            Vendor = 4,
-            Controller = 5,
-            Bmc = 6,
+            pci = 1,
+            pc_card = 2,
+            memory_mapped = 3,
+            vendor = 4,
+            controller = 5,
+            bmc = 6,
             _,
         };
 
@@ -151,14 +151,14 @@ pub const DevicePath = union(Type) {
     };
 
     pub const Acpi = union(Subtype) {
-        Acpi: *const BaseAcpiDevicePath,
-        ExpandedAcpi: *const ExpandedAcpiDevicePath,
-        Adr: *const AdrDevicePath,
+        acpi: *const BaseAcpiDevicePath,
+        expanded_acpi: *const ExpandedAcpiDevicePath,
+        adr: *const AdrDevicePath,
 
         pub const Subtype = enum(u8) {
-            Acpi = 1,
-            ExpandedAcpi = 2,
-            Adr = 3,
+            acpi = 1,
+            expanded_acpi = 2,
+            adr = 3,
             _,
         };
 

lib/std/pdb.zig

@@ -399,17 +399,14 @@ pub const LineBlockFragmentHeader = extern struct {
 pub const LineNumberEntry = extern struct {
     /// Offset to start of code bytes for line number
     Offset: u32,
-    Flags: u32,
-
-    /// TODO runtime crash when I make the actual type of Flags this
-    pub const Flags = packed struct {
+    Flags: packed struct(u32) {
         /// Start line number
         Start: u24,
         /// Delta of lines to the end of the expression. Still unclear.
         // TODO figure out the point of this field.
         End: u7,
         IsStatement: bool,
-    };
+    },
 };
 
 pub const ColumnNumberEntry = extern struct {