Compiling to Wasm doesn't include exports by default, at least while doing it on macOS.

[icylace]

Zig Version

0.11.0-dev.1017+d86685ac9

Steps to Reproduce and Observed Behavior

I'm running a MacBook Pro 16-inch from 2019 with macOS Ventura 13.1.

0. Install the latest version of Zig for macOS using Homebrew:

   $ brew install zig --HEAD

1. Create an add.zig file having this code:

   export fn add(x: i32, y: i32) i32 {
       return x + y;
   }

2. Compile it to Wasm:

   $ zig build-lib add.zig -target wasm32-freestanding -dynamic

3. Inspect the generated Wasm file with wasm2wat:

   $ wasm2wat add.wasm
   
   (module
     (memory (;0;) 16)
     (global $__stack_pointer (mut i32) (i32.const 1048576))
     (export "memory" (memory 0)))

   Notice the add() function is missing !

4. However, if we recompile while forcing the export with --export=add it will work. For brevity of output, let's also use -O ReleaseSmall:

   $ zig build-lib add.zig -target wasm32-freestanding -dynamic -O ReleaseSmall --export=add

5. Again, inspect the generated Wasm with wasm2wat:

   $ wasm2wat add.wasm
   
   (module
     (type (;0;) (func (param i32 i32) (result i32)))
     (func (;0;) (type 0) (param i32 i32) (result i32)
       local.get 1
       local.get 0
       i32.add)
     (memory (;0;) 16)
     (global (;0;) (mut i32) (i32.const 1048576))
     (export "memory" (memory 0))
     (export "add" (func 0)))

   Finally a good result but we were forced to export explicitly on the command line. This would be a pain if we had many things to export.

Expected Behavior

My expectation is that running:

$ zig build-lib add.zig -target wasm32-freestanding -dynamic

will produce a Wasm file that includes the add() function.

To put it in general terms, all exports should actually be exported by default.

[schmee]

This is an intentional (breaking) change, see #14102.

[icylace]

I see, so the solution for my situation is to include -rdynamic:

$ zig build-lib add.zig -target wasm32-freestanding -dynamic -rdynamic -O ReleaseSmall

$ wasm2wat add.wasm

(module
  (type (;0;) (func (param i32 i32) (result i32)))
  (func (;0;) (type 0) (param i32 i32) (result i32)
    local.get 1
    local.get 0
    i32.add)
  (memory (;0;) 16)
  (global (;0;) (mut i32) (i32.const 1048576))
  (export "memory" (memory 0))
  (export "add" (func 0)))

That works for me. Thanks, @schmee !