Auto merge of #128378 - matthiaskrgr:rollup-i3qz9uo, r=matthiaskrgr

Rollup of 4 pull requests

Successful merges:

 - #127574 (elaborate unknowable goals)
 - #128141 (Set branch protection function attributes)
 - #128315 (Fix vita build of std and forbid unsafe in unsafe in the os/vita module)
 - #128339 ([rustdoc] Make the buttons remain when code example is clicked)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -5,7 +5,7 @@ use rustc_codegen_ssa::traits::*;
 use rustc_hir::def_id::DefId;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, PatchableFunctionEntry};
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_session::config::{FunctionReturn, OptLevel};
+use rustc_session::config::{BranchProtection, FunctionReturn, OptLevel, PAuthKey, PacRet};
 use rustc_span::symbol::sym;
 use rustc_target::spec::{FramePointer, SanitizerSet, StackProbeType, StackProtector};
 use smallvec::SmallVec;
@@ -405,8 +405,33 @@ pub fn from_fn_attrs<'ll, 'tcx>(
         // And it is a module-level attribute, so the alternative is pulling naked functions into new LLVM modules.
         // Otherwise LLVM's "naked" functions come with endbr prefixes per https://github.com/rust-lang/rust/issues/98768
         to_add.push(AttributeKind::NoCfCheck.create_attr(cx.llcx));
-        // Need this for AArch64.
-        to_add.push(llvm::CreateAttrStringValue(cx.llcx, "branch-target-enforcement", "false"));
+        if llvm_util::get_version() < (19, 0, 0) {
+            // Prior to LLVM 19, branch-target-enforcement was disabled by setting the attribute to
+            // the string "false". Now it is disabled by absence of the attribute.
+            to_add.push(llvm::CreateAttrStringValue(cx.llcx, "branch-target-enforcement", "false"));
+        }
+    } else if llvm_util::get_version() >= (19, 0, 0) {
+        // For non-naked functions, set branch protection attributes on aarch64.
+        if let Some(BranchProtection { bti, pac_ret }) =
+            cx.sess().opts.unstable_opts.branch_protection
+        {
+            assert!(cx.sess().target.arch == "aarch64");
+            if bti {
+                to_add.push(llvm::CreateAttrString(cx.llcx, "branch-target-enforcement"));
+            }
+            if let Some(PacRet { leaf, key }) = pac_ret {
+                to_add.push(llvm::CreateAttrStringValue(
+                    cx.llcx,
+                    "sign-return-address",
+                    if leaf { "all" } else { "non-leaf" },
+                ));
+                to_add.push(llvm::CreateAttrStringValue(
+                    cx.llcx,
+                    "sign-return-address-key",
+                    if key == PAuthKey::A { "a_key" } else { "b_key" },
+                ));
+            }
+        }
     }
     if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::ALLOCATOR)
         || codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::ALLOCATOR_ZEROED)

compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs

@@ -698,6 +698,18 @@ where
                 if ecx.trait_ref_is_knowable(goal.param_env, trait_ref)? {
                     Err(NoSolution)
                 } else {
+                    // While the trait bound itself may be unknowable, we may be able to
+                    // prove that a super trait is not implemented. For this, we recursively
+                    // prove the super trait bounds of the current goal.
+                    //
+                    // We skip the goal itself as that one would cycle.
+                    let predicate: I::Predicate = trait_ref.upcast(cx);
+                    ecx.add_goals(
+                        GoalSource::Misc,
+                        elaborate::elaborate(cx, [predicate])
+                            .skip(1)
+                            .map(|predicate| goal.with(cx, predicate)),
+                    );
                     ecx.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS)
                 }
             },

compiler/rustc_type_ir/src/inherent.rs

@@ -432,6 +432,7 @@ pub trait Predicate<I: Interner<Predicate = Self>>:
     + UpcastFrom<I, ty::OutlivesPredicate<I, I::Ty>>
     + UpcastFrom<I, ty::OutlivesPredicate<I, I::Region>>
     + IntoKind<Kind = ty::Binder<I, ty::PredicateKind<I>>>
+    + Elaboratable<I>
 {
     fn as_clause(self) -> Option<I::Clause>;
 

library/std/src/os/vita/mod.rs

@@ -1,5 +1,6 @@
 //! Definitions for vita
 
+#![forbid(unsafe_op_in_unsafe_fn)]
 #![stable(feature = "raw_ext", since = "1.1.0")]
 
 pub mod fs;

library/std/src/os/vita/raw.rs

@@ -10,9 +10,6 @@
 )]
 #![allow(deprecated)]
 
-use crate::os::raw::c_long;
-use crate::os::unix::raw::{gid_t, uid_t};
-
 #[stable(feature = "pthread_t", since = "1.8.0")]
 pub type pthread_t = libc::pthread_t;
 
@@ -34,37 +31,3 @@ pub type off_t = libc::off_t;
 
 #[stable(feature = "raw_ext", since = "1.1.0")]
 pub type time_t = libc::time_t;
-
-#[repr(C)]
-#[derive(Clone)]
-#[stable(feature = "raw_ext", since = "1.1.0")]
-pub struct stat {
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_dev: dev_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_ino: ino_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_mode: mode_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_nlink: nlink_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_uid: uid_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_gid: gid_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_rdev: dev_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_size: off_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_atime: time_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_mtime: time_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_ctime: time_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_blksize: blksize_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_blocks: blkcnt_t,
-    #[stable(feature = "raw_ext", since = "1.1.0")]
-    pub st_spare4: [c_long; 2usize],
-}

library/std/src/sys/pal/unix/mod.rs

@@ -166,6 +166,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
             target_os = "fuchsia",
             target_os = "horizon",
             target_os = "vxworks",
+            target_os = "vita",
             // Unikraft's `signal` implementation is currently broken:
             // https://github.com/unikraft/lib-musl/issues/57
             target_vendor = "unikraft",
@@ -212,6 +213,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
     target_os = "fuchsia",
     target_os = "horizon",
     target_os = "vxworks",
+    target_os = "vita",
 )))]
 static ON_BROKEN_PIPE_FLAG_USED: crate::sync::atomic::AtomicBool =
     crate::sync::atomic::AtomicBool::new(false);
@@ -222,6 +224,7 @@ static ON_BROKEN_PIPE_FLAG_USED: crate::sync::atomic::AtomicBool =
     target_os = "fuchsia",
     target_os = "horizon",
     target_os = "vxworks",
+    target_os = "vita",
 )))]
 pub(crate) fn on_broken_pipe_flag_used() -> bool {
     ON_BROKEN_PIPE_FLAG_USED.load(crate::sync::atomic::Ordering::Relaxed)

library/std/src/sys/pal/unix/process/process_common.rs

@@ -124,6 +124,7 @@ pub struct StdioPipes {
 
 // passed to do_exec() with configuration of what the child stdio should look
 // like
+#[cfg_attr(target_os = "vita", allow(dead_code))]
 pub struct ChildPipes {
     pub stdin: ChildStdio,
     pub stdout: ChildStdio,

src/librustdoc/html/static/css/rustdoc.css

@@ -1477,7 +1477,20 @@ a.test-arrow:hover {
 .example-wrap:hover > .test-arrow {
 	padding: 2px 7px;
 }
-.example-wrap:hover > .test-arrow, .example-wrap:hover > .button-holder {
+/*
+On iPad, the ":hover" state sticks around, making things work not greatly. Do work around
+it, we move it into this media query. More information can be found at:
+https://css-tricks.com/solving-sticky-hover-states-with-media-hover-hover/
+
+However, using `@media (hover: hover)` makes this rule never to be applied in GUI tests, so
+instead, we check that it's not a "finger" cursor.
+*/
+@media not (pointer: coarse) {
+	.example-wrap:hover > .test-arrow, .example-wrap:hover > .button-holder {
+		visibility: visible;
+	}
+}
+.example-wrap .button-holder.keep-visible {
 	visibility: visible;
 }
 .example-wrap .button-holder .copy-button {

src/librustdoc/html/static/js/main.js

@@ -1829,14 +1829,22 @@ href="https://doc.rust-lang.org/${channel}/rustdoc/read-documentation/search.htm
         copyContentToClipboard(codeElem.textContent);
     }
 
-    function addCopyButton(event) {
+    function getExampleWrap(event) {
         let elem = event.target;
         while (!hasClass(elem, "example-wrap")) {
             elem = elem.parentElement;
             if (elem.tagName === "body" || hasClass(elem, "docblock")) {
-                return;
+                return null;
             }
         }
+        return elem;
+    }
+
+    function addCopyButton(event) {
+        const elem = getExampleWrap(event);
+        if (elem === null) {
+            return;
+        }
         // Since the button will be added, no need to keep this listener around.
         elem.removeEventListener("mouseover", addCopyButton);
 
@@ -1858,7 +1866,20 @@ href="https://doc.rust-lang.org/${channel}/rustdoc/read-documentation/search.htm
         parent.appendChild(copyButton);
     }
 
+    function showHideCodeExampleButtons(event) {
+        const elem = getExampleWrap(event);
+        if (elem === null) {
+            return;
+        }
+        const buttons = elem.querySelector(".button-holder");
+        if (buttons === null) {
+            return;
+        }
+        buttons.classList.toggle("keep-visible");
+    }
+
     onEachLazy(document.querySelectorAll(".docblock .example-wrap"), elem => {
         elem.addEventListener("mouseover", addCopyButton);
+        elem.addEventListener("click", showHideCodeExampleButtons);
     });
 }());

tests/codegen/branch-protection-old-llvm.rs

@@ -0,0 +1,45 @@
+// Test that the correct module flags are emitted with different branch protection flags.
+
+//@ revisions: BTI PACRET LEAF BKEY NONE
+//@ needs-llvm-components: aarch64
+//@ [BTI] compile-flags: -Z branch-protection=bti
+//@ [PACRET] compile-flags: -Z branch-protection=pac-ret
+//@ [LEAF] compile-flags: -Z branch-protection=pac-ret,leaf
+//@ [BKEY] compile-flags: -Z branch-protection=pac-ret,b-key
+//@ compile-flags: --target aarch64-unknown-linux-gnu
+//@ ignore-llvm-version: 19 - 99
+
+#![crate_type = "lib"]
+#![feature(no_core, lang_items)]
+#![no_core]
+
+#[lang = "sized"]
+trait Sized {}
+
+// A basic test function.
+pub fn test() {}
+
+// BTI: !"branch-target-enforcement", i32 1
+// BTI: !"sign-return-address", i32 0
+// BTI: !"sign-return-address-all", i32 0
+// BTI: !"sign-return-address-with-bkey", i32 0
+
+// PACRET: !"branch-target-enforcement", i32 0
+// PACRET: !"sign-return-address", i32 1
+// PACRET: !"sign-return-address-all", i32 0
+// PACRET: !"sign-return-address-with-bkey", i32 0
+
+// LEAF: !"branch-target-enforcement", i32 0
+// LEAF: !"sign-return-address", i32 1
+// LEAF: !"sign-return-address-all", i32 1
+// LEAF: !"sign-return-address-with-bkey", i32 0
+
+// BKEY: !"branch-target-enforcement", i32 0
+// BKEY: !"sign-return-address", i32 1
+// BKEY: !"sign-return-address-all", i32 0
+// BKEY: !"sign-return-address-with-bkey", i32 1
+
+// NONE-NOT: branch-target-enforcement
+// NONE-NOT: sign-return-address
+// NONE-NOT: sign-return-address-all
+// NONE-NOT: sign-return-address-with-bkey