align cast result of flexible array member function

Closes #211

Author: Vexu

src/Translator.zig

@@ -3980,7 +3980,8 @@ fn createFlexibleMemberFn(
 
     // return @ptrCast(&self.*.<field_name>);
     const address_of = try ZigTag.address_of.create(t.arena, field_access);
-    const casted = try ZigTag.ptr_cast.create(t.arena, address_of);
+    const aligned = try ZigTag.align_cast.create(t.arena, address_of);
+    const casted = try ZigTag.ptr_cast.create(t.arena, aligned);
     const return_stmt = try ZigTag.@"return".create(t.arena, casted);
     const body = try ZigTag.block_single.create(t.arena, return_stmt);
 

test/cases/translate/struct_with_flexible_array.c

@@ -7,13 +7,13 @@ struct bar { int x; int y[0]; };
 //     x: c_int = 0,
 //     _y: [0]c_int = @import("std").mem.zeroes([0]c_int),
 //     pub fn y(self: anytype) __helpers.FlexibleArrayType(@TypeOf(self), @typeInfo(@TypeOf(self.*._y)).array.child) {
-//         return @ptrCast(&self.*._y);
+//         return @ptrCast(@alignCast(&self.*._y));
 //     }
 // };
 // pub const struct_bar = extern struct {
 //     x: c_int = 0,
 //     _y: [0]c_int = @import("std").mem.zeroes([0]c_int),
 //     pub fn y(self: anytype) __helpers.FlexibleArrayType(@TypeOf(self), @typeInfo(@TypeOf(self.*._y)).array.child) {
-//         return @ptrCast(&self.*._y);
+//         return @ptrCast(@alignCast(&self.*._y));
 //     }
 // };