stage2: fix the build for 32-bit architectures

 * Introduce a mechanism into Sema for emitting a compile error when an
   integer is too big and we need it to fit into a usize.
 * Add `@intCast` where necessary
 * link/MachO: fix an unnecessary allocation when all that was happening
   was appending zeroes to an ArrayList.
 * Add `error.Overflow` as a possible error to some codepaths, allowing
   usage of `math.intCast`.

closes #9710

1 files changed, 4 insertions, 2 deletions

diff --git a/src/Module.zig b/src/Module.zig
index cc5209a217..33b3c43423 100644
--- a/src/Module.zig
+++ b/src/Module.zig
@@ -3661,7 +3661,8 @@ pub fn embedFile(mod: *Module, cur_file: *File, rel_file_path: []const u8) !*Emb
     defer file.close();
 
     const stat = try file.stat();
-    const bytes = try file.readToEndAllocOptions(gpa, std.math.maxInt(u32), stat.size, 1, 0);
+    const size_usize = try std.math.cast(usize, stat.size);
+    const bytes = try file.readToEndAllocOptions(gpa, std.math.maxInt(u32), size_usize, 1, 0);
 
     log.debug("new embedFile. resolved_root_path={s}, resolved_path={s}, sub_file_path={s}, rel_file_path={s}", .{
         resolved_root_path, resolved_path, sub_file_path, rel_file_path,
@@ -3694,7 +3695,8 @@ pub fn detectEmbedFileUpdate(mod: *Module, embed_file: *EmbedFile) !void {
     if (unchanged_metadata) return;
 
     const gpa = mod.gpa;
-    const bytes = try file.readToEndAllocOptions(gpa, std.math.maxInt(u32), stat.size, 1, 0);
+    const size_usize = try std.math.cast(usize, stat.size);
+    const bytes = try file.readToEndAllocOptions(gpa, std.math.maxInt(u32), size_usize, 1, 0);
     gpa.free(embed_file.bytes);
     embed_file.bytes = bytes;
     embed_file.stat_size = stat.size;