Enable noprelude uncondtionally

Summary:
We were conditionally adding `noprelude`, which was resulting in a difference in behavior as compared to cargo builds.

1. In cargo, all std library crates are attached using `noprelude` https://github.com/rust-lang/cargo/blob/12541d6e5ef095b03035bb316461890b40db10f4/src/cargo/core/compiler/unit_dependencies.rs#L185.
2. When actually compiling the crate, `rustc` will inject the correct prelude (depending on `no_std`, `no_core`, etc) https://github.com/rust-lang/rust/blob/243d2ca4db6f96d2d18aaf3a2381251d38eb6b0b/src/tools/rust-analyzer/crates/hir-def/src/nameres/collector.rs#L488

Given (2), it is more correct for us to follow the same pattern as `cargo` and unconditionally apply `"noprelude"`.

Reviewed By: dtolnay

Differential Revision: D67805532

fbshipit-source-id: 05bfc8d85e1f3d749e92420f8bd8fe160d2210a2

prelude/rust/link_info.bzl

@@ -269,20 +269,22 @@ def gather_explicit_sysroot_deps(dep_ctx: DepCollectionContext) -> list[RustOrNa
         out.append(RustOrNativeDependency(
             dep = explicit_sysroot_deps.core,
             name = None,
-            flags = ["nounused"],
+            flags = ["noprelude", "nounused"],
         ))
     if explicit_sysroot_deps.std:
         out.append(RustOrNativeDependency(
             dep = explicit_sysroot_deps.std,
             name = None,
-            flags = ["nounused", "force"],
+            # "force" is used here in order to link std internals (like alloc hooks) even if the rest
+            # of std is otherwise unused (e.g. we are building a no_std crate that needs to link with
+            # other std-enabled crates as a standalone dylib).
+            flags = ["noprelude", "nounused", "force"],
         ))
     if explicit_sysroot_deps.proc_macro:
-        flags = ["noprelude"] if not dep_ctx.is_proc_macro or dep_ctx.include_doc_deps else []
         out.append(RustOrNativeDependency(
             dep = explicit_sysroot_deps.proc_macro,
             name = None,
-            flags = ["nounused"] + flags,
+            flags = ["noprelude", "nounused"],
         ))
 
     # When advanced_unstable_linking is on, we only add the dep that matches the
@@ -293,19 +295,16 @@ def gather_explicit_sysroot_deps(dep_ctx: DepCollectionContext) -> list[RustOrNa
             out.append(RustOrNativeDependency(
                 dep = explicit_sysroot_deps.panic_unwind,
                 name = None,
-                flags = ["nounused"],
+                flags = ["noprelude", "nounused"],
             ))
     if explicit_sysroot_deps.panic_abort:
         if not dep_ctx.advanced_unstable_linking or dep_ctx.panic_runtime == PanicRuntime("abort"):
             out.append(RustOrNativeDependency(
                 dep = explicit_sysroot_deps.panic_abort,
                 name = None,
-                flags = ["nounused"],
+                flags = ["noprelude", "nounused"],
             ))
     for d in explicit_sysroot_deps.others:
-        # FIXME(JakobDegen): Ideally we would not be using `noprelude` here but
-        # instead report these as regular transitive dependencies. However,
-        # that's a bit harder to get right, so leave it like this for now.
         out.append(RustOrNativeDependency(
             dep = d,
             name = None,