lib: c allocator can use fromZig

src/lib/allocator.zig

@@ -216,89 +216,8 @@ const ZigAllocator = struct {
     }
 };
 
-/// C allocator (libc)
+/// libc Allocator, requires linking libc
-pub const CAllocator = struct {
+pub const c_allocator: Allocator = .fromZig(&std.heap.c_allocator);
-    comptime {
-        if (!builtin.link_libc) {
-            @compileError("C allocator is only available when linking against libc");
-        }
-    }
-
-    const vtable: VTable = .{
-        .alloc = alloc,
-        .resize = resize,
-        .remap = remap,
-        .free = free,
-    };
-
-    fn alloc(
-        ctx: *anyopaque,
-        len: usize,
-        alignment: u8,
-        ra: usize,
-    ) callconv(.c) ?[*]u8 {
-        return std.heap.c_allocator.vtable.alloc(
-            ctx,
-            len,
-            @enumFromInt(alignment),
-            ra,
-        );
-    }
-
-    fn resize(
-        ctx: *anyopaque,
-        memory: [*]u8,
-        memory_len: usize,
-        alignment: u8,
-        new_len: usize,
-        ra: usize,
-    ) callconv(.c) bool {
-        return std.heap.c_allocator.vtable.resize(
-            ctx,
-            memory[0..memory_len],
-            @enumFromInt(alignment),
-            new_len,
-            ra,
-        );
-    }
-
-    fn remap(
-        ctx: *anyopaque,
-        memory: [*]u8,
-        memory_len: usize,
-        alignment: u8,
-        new_len: usize,
-        ra: usize,
-    ) callconv(.c) ?[*]u8 {
-        return std.heap.c_allocator.vtable.remap(
-            ctx,
-            memory[0..memory_len],
-            @enumFromInt(alignment),
-            new_len,
-            ra,
-        );
-    }
-
-    fn free(
-        ctx: *anyopaque,
-        memory: [*]u8,
-        memory_len: usize,
-        alignment: u8,
-        ra: usize,
-    ) callconv(.c) void {
-        std.heap.c_allocator.vtable.free(
-            ctx,
-            memory[0..memory_len],
-            @enumFromInt(alignment),
-            ra,
-        );
-    }
-};
-
-pub const c_allocator: Allocator = .{
-    .ctx = undefined,
-    .vtable = &CAllocator.vtable,
-};
 
 /// Allocator that can be sent to the C API that does full
 /// leak checking within Zig tests. This should only be used from