Give some more intrinsics fallback bodies

compiler/rustc_hir_analysis/src/check/intrinsic.rs

@@ -222,7 +222,7 @@ pub fn check_intrinsic_type(
             sym::caller_location => (0, 0, vec![], tcx.caller_location_ty()),
             sym::assert_inhabited
             | sym::assert_zero_valid
-            | sym::assert_mem_uninitialized_valid => (1, 0, vec![], Ty::new_unit(tcx)),
+            | sym::assert_mem_uninitialized_valid => (1, 1, vec![], Ty::new_unit(tcx)),
             sym::forget => (1, 0, vec![param(0)], Ty::new_unit(tcx)),
             sym::transmute | sym::transmute_unchecked => (2, 0, vec![param(0)], param(1)),
             sym::prefetch_read_data

tests/ui/intrinsics/safe-intrinsic-mismatch.rs

@@ -5,12 +5,12 @@
 extern "rust-intrinsic" {
     fn size_of<T>() -> usize; //~ ERROR intrinsic safety mismatch
     //~^ ERROR intrinsic safety mismatch
-
-    #[rustc_safe_intrinsic]
-    fn assume(b: bool); //~ ERROR intrinsic safety mismatch
-    //~^ ERROR intrinsic safety mismatch
 }
 
+#[rustc_intrinsic]
+const fn assume(_b: bool) {} //~ ERROR intrinsic safety mismatch
+//~| ERROR intrinsic has wrong type
+
 #[rustc_intrinsic]
 const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
 //~^ ERROR intrinsic safety mismatch

tests/ui/intrinsics/safe-intrinsic-mismatch.stderr

@@ -4,12 +4,6 @@ error: intrinsic safety mismatch between list of intrinsics within the compiler
 LL |     fn size_of<T>() -> usize;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `assume`
-  --> $DIR/safe-intrinsic-mismatch.rs:10:5
-   |
-LL |     fn assume(b: bool);
-   |     ^^^^^^^^^^^^^^^^^^
-
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `size_of`
   --> $DIR/safe-intrinsic-mismatch.rs:6:5
    |
@@ -19,12 +13,19 @@ LL |     fn size_of<T>() -> usize;
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `assume`
-  --> $DIR/safe-intrinsic-mismatch.rs:10:5
+  --> $DIR/safe-intrinsic-mismatch.rs:11:1
    |
-LL |     fn assume(b: bool);
-   |     ^^^^^^^^^^^^^^^^^^
+LL | const fn assume(_b: bool) {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0308]: intrinsic has wrong type
+  --> $DIR/safe-intrinsic-mismatch.rs:11:16
    |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+LL | const fn assume(_b: bool) {}
+   |                ^ expected unsafe fn, found normal fn
+   |
+   = note: expected signature `unsafe fn(_)`
+              found signature `fn(_)`
 
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `const_deallocate`
   --> $DIR/safe-intrinsic-mismatch.rs:15:1

tests/ui/reify-intrinsic.rs

@@ -13,10 +13,9 @@ fn b() {
 }
 
 fn c() {
-    let _ = [
-        std::intrinsics::likely,
+    let _: [unsafe extern "rust-intrinsic" fn(bool) -> bool; 2] = [
+        std::intrinsics::likely, //~ ERROR cannot coerce
         std::intrinsics::unlikely,
-        //~^ ERROR cannot coerce
     ];
 }
 

tests/ui/reify-intrinsic.stderr

@@ -16,14 +16,13 @@ LL |     let _ = std::mem::transmute as unsafe extern "rust-intrinsic" fn(isize)
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0308]: cannot coerce intrinsics to function pointers
-  --> $DIR/reify-intrinsic.rs:18:9
+  --> $DIR/reify-intrinsic.rs:17:9
    |
-LL |         std::intrinsics::unlikely,
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ cannot coerce intrinsics to function pointers
+LL |         std::intrinsics::likely,
+   |         ^^^^^^^^^^^^^^^^^^^^^^^ cannot coerce intrinsics to function pointers
    |
-   = note: expected fn item `extern "rust-intrinsic" fn(_) -> _ {likely}`
-              found fn item `extern "rust-intrinsic" fn(_) -> _ {unlikely}`
-   = note: different fn items have unique types, even if their signatures are the same
+   = note: expected fn pointer `unsafe extern "rust-intrinsic" fn(_) -> _`
+                 found fn item `fn(_) -> _ {likely}`
 
 error: aborting due to 3 previous errors