Remove the insta-stable `cfg(wasm)`

The addition of `cfg(wasm)` was an oversight on my end that has a number
of downsides:

* It was introduced as an insta-stable addition, forgoing the usual
  staging mechanism we use for potentially far-reaching changes;
* It is a breaking change for people who are using `--cfg wasm` either
  directly or via cargo for other purposes;
* It is not entirely clear if a bare `wasm` cfg is a right option or
  whether `wasm` family of targets are special enough to warrant
  special-casing these targets specifically.

As for the last point, there appears to be a fair amount of support for
reducing the boilerplate in specifying architectures from the same
family, while ignoring their pointer width. The suggested way forward
would be to propose such a change as a separate RFC as it is potentially
a quite contentious addition.

1 files changed, 0 insertions, 3 deletions

diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index ec04bf7d054..75bd8880b34 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -822,9 +822,6 @@ pub fn default_configuration(sess: &Session) -> CrateConfig {
         }
     }
     ret.insert((sym::target_arch, Some(Symbol::intern(arch))));
-    if sess.target.is_like_wasm {
-        ret.insert((sym::wasm, None));
-    }
     ret.insert((sym::target_endian, Some(Symbol::intern(end.as_str()))));
     ret.insert((sym::target_pointer_width, Some(Symbol::intern(&wordsz))));
     ret.insert((sym::target_env, Some(Symbol::intern(env))));