Gracefully handle non-UTF-8 string slices when pretty printing

diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index fbf30b58818f31b9a73a1e2f2b086a3d3de51db5..636b571a922c11c3179633cb13592e6b9cf79493 100644 (file)
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -1443,8 +1443,7 @@ fn pretty_print_const_value(
                 // relocations (we have an active `str` reference here). We don't use this
                 // result to affect interpreter execution.
                 let slice = data.inspect_with_uninit_and_ptr_outside_interpreter(start..end);
-                let s = std::str::from_utf8(slice).expect("non utf8 str from miri");
-                p!(write("{:?}", s));
+                p!(write("{:?}", String::from_utf8_lossy(slice)));
                 Ok(self)
             }
             (ConstValue::ByRef { alloc, offset }, ty::Array(t, n)) if *t == u8_type => {

diff --git a/src/test/mir-opt/const_prop/invalid_constant.main.ConstProp.diff b/src/test/mir-opt/const_prop/invalid_constant.main.ConstProp.diff
index 03f827f63f37fe43be26ff06ffea1a069d249d7d..9480566897f8d1003e0d6dbd2f0416ae0868ec34 100644 (file)
--- a/src/test/mir-opt/const_prop/invalid_constant.main.ConstProp.diff
+++ b/src/test/mir-opt/const_prop/invalid_constant.main.ConstProp.diff
@@ -2,63 +2,69 @@
 + // MIR for `main` after ConstProp
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/invalid_constant.rs:13:11: 13:11
-      let _1: main::InvalidChar;           // in scope 0 at $DIR/invalid_constant.rs:19:9: 19:22
-      let mut _3: main::InvalidTag;        // in scope 0 at $DIR/invalid_constant.rs:26:25: 26:46
-      let mut _5: main::NoVariants;        // in scope 0 at $DIR/invalid_constant.rs:33:35: 33:56
+      let mut _0: ();                      // return place in scope 0 at $DIR/invalid_constant.rs:15:11: 15:11
+      let _1: main::InvalidChar;           // in scope 0 at $DIR/invalid_constant.rs:21:9: 21:22
+      let mut _3: main::InvalidTag;        // in scope 0 at $DIR/invalid_constant.rs:28:25: 28:46
+      let mut _5: main::NoVariants;        // in scope 0 at $DIR/invalid_constant.rs:35:35: 35:56
       scope 1 {
-          debug _invalid_char => _1;       // in scope 1 at $DIR/invalid_constant.rs:19:9: 19:22
-          let _2: [main::InvalidTag; 1];   // in scope 1 at $DIR/invalid_constant.rs:26:9: 26:21
+          debug _invalid_char => _1;       // in scope 1 at $DIR/invalid_constant.rs:21:9: 21:22
+          let _2: [main::InvalidTag; 1];   // in scope 1 at $DIR/invalid_constant.rs:28:9: 28:21
           scope 2 {
-              debug _invalid_tag => _2;    // in scope 2 at $DIR/invalid_constant.rs:26:9: 26:21
-              let _4: [main::NoVariants; 1]; // in scope 2 at $DIR/invalid_constant.rs:33:9: 33:31
+              debug _invalid_tag => _2;    // in scope 2 at $DIR/invalid_constant.rs:28:9: 28:21
+              let _4: [main::NoVariants; 1]; // in scope 2 at $DIR/invalid_constant.rs:35:9: 35:31
               scope 3 {
-                  debug _enum_without_variants => _4; // in scope 3 at $DIR/invalid_constant.rs:33:9: 33:31
+                  debug _enum_without_variants => _4; // in scope 3 at $DIR/invalid_constant.rs:35:9: 35:31
+                  let _6: main::Str<"���">; // in scope 3 at $DIR/invalid_constant.rs:39:9: 39:22
+                  scope 4 {
+                      debug _non_utf8_str => _6; // in scope 4 at $DIR/invalid_constant.rs:39:9: 39:22
+                  }
               }
           }
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/invalid_constant.rs:19:9: 19:22
--         _1 = const { InvalidChar { int: 0x110001 } }; // scope 0 at $DIR/invalid_constant.rs:19:25: 19:64
-+         _1 = const InvalidChar { int: 1114113_u32, chr: {transmute(0x00110001): char} }; // scope 0 at $DIR/invalid_constant.rs:19:25: 19:64
+          StorageLive(_1);                 // scope 0 at $DIR/invalid_constant.rs:21:9: 21:22
+-         _1 = const { InvalidChar { int: 0x110001 } }; // scope 0 at $DIR/invalid_constant.rs:21:25: 21:64
++         _1 = const InvalidChar { int: 1114113_u32, chr: {transmute(0x00110001): char} }; // scope 0 at $DIR/invalid_constant.rs:21:25: 21:64
                                            // ty::Const
                                            // + ty: main::InvalidChar
 -                                          // + val: Unevaluated(main::{constant#0}, [main::InvalidChar], None)
 +                                          // + val: Value(Scalar(0x00110001))
                                            // mir::Constant
-                                           // + span: $DIR/invalid_constant.rs:19:25: 19:64
+                                           // + span: $DIR/invalid_constant.rs:21:25: 21:64
 -                                          // + literal: Const { ty: main::InvalidChar, val: Unevaluated(Unevaluated { def: WithOptConstParam { did: DefId(0:7 ~ invalid_constant[726d]::main::{constant#0}), const_param_did: None }, substs: [main::InvalidChar], promoted: None }) }
 +                                          // + literal: Const { ty: main::InvalidChar, val: Value(Scalar(0x00110001)) }
-          StorageLive(_2);                 // scope 1 at $DIR/invalid_constant.rs:26:9: 26:21
-          StorageLive(_3);                 // scope 1 at $DIR/invalid_constant.rs:26:25: 26:46
-          (_3.0: u32) = const 4_u32;       // scope 1 at $DIR/invalid_constant.rs:26:25: 26:46
--         _2 = [move _3];                  // scope 1 at $DIR/invalid_constant.rs:26:24: 26:47
-+         _2 = [const InvalidTag { int: 4_u32, e: Scalar(0x00000004): E }]; // scope 1 at $DIR/invalid_constant.rs:26:24: 26:47
+          StorageLive(_2);                 // scope 1 at $DIR/invalid_constant.rs:28:9: 28:21
+          StorageLive(_3);                 // scope 1 at $DIR/invalid_constant.rs:28:25: 28:46
+          (_3.0: u32) = const 4_u32;       // scope 1 at $DIR/invalid_constant.rs:28:25: 28:46
+-         _2 = [move _3];                  // scope 1 at $DIR/invalid_constant.rs:28:24: 28:47
++         _2 = [const InvalidTag { int: 4_u32, e: Scalar(0x00000004): E }]; // scope 1 at $DIR/invalid_constant.rs:28:24: 28:47
 +                                          // ty::Const
 +                                          // + ty: main::InvalidTag
 +                                          // + val: Value(Scalar(0x00000004))
 +                                          // mir::Constant
-+                                          // + span: $DIR/invalid_constant.rs:26:24: 26:47
++                                          // + span: $DIR/invalid_constant.rs:28:24: 28:47
 +                                          // + literal: Const { ty: main::InvalidTag, val: Value(Scalar(0x00000004)) }
-          StorageDead(_3);                 // scope 1 at $DIR/invalid_constant.rs:26:46: 26:47
-          StorageLive(_4);                 // scope 2 at $DIR/invalid_constant.rs:33:9: 33:31
-          StorageLive(_5);                 // scope 2 at $DIR/invalid_constant.rs:33:35: 33:56
-          (_5.0: u32) = const 0_u32;       // scope 2 at $DIR/invalid_constant.rs:33:35: 33:56
--         _4 = [move _5];                  // scope 2 at $DIR/invalid_constant.rs:33:34: 33:57
-+         _4 = [const NoVariants { int: 0_u32, empty: Scalar(<ZST>): Empty }]; // scope 2 at $DIR/invalid_constant.rs:33:34: 33:57
+          StorageDead(_3);                 // scope 1 at $DIR/invalid_constant.rs:28:46: 28:47
+          StorageLive(_4);                 // scope 2 at $DIR/invalid_constant.rs:35:9: 35:31
+          StorageLive(_5);                 // scope 2 at $DIR/invalid_constant.rs:35:35: 35:56
+          (_5.0: u32) = const 0_u32;       // scope 2 at $DIR/invalid_constant.rs:35:35: 35:56
+-         _4 = [move _5];                  // scope 2 at $DIR/invalid_constant.rs:35:34: 35:57
++         _4 = [const NoVariants { int: 0_u32, empty: Scalar(<ZST>): Empty }]; // scope 2 at $DIR/invalid_constant.rs:35:34: 35:57
 +                                          // ty::Const
 +                                          // + ty: main::NoVariants
 +                                          // + val: Value(Scalar(0x00000000))
 +                                          // mir::Constant
-+                                          // + span: $DIR/invalid_constant.rs:33:34: 33:57
++                                          // + span: $DIR/invalid_constant.rs:35:34: 35:57
 +                                          // + literal: Const { ty: main::NoVariants, val: Value(Scalar(0x00000000)) }
-          StorageDead(_5);                 // scope 2 at $DIR/invalid_constant.rs:33:56: 33:57
-          nop;                             // scope 0 at $DIR/invalid_constant.rs:13:11: 34:2
-          StorageDead(_4);                 // scope 2 at $DIR/invalid_constant.rs:34:1: 34:2
-          StorageDead(_2);                 // scope 1 at $DIR/invalid_constant.rs:34:1: 34:2
-          StorageDead(_1);                 // scope 0 at $DIR/invalid_constant.rs:34:1: 34:2
-          return;                          // scope 0 at $DIR/invalid_constant.rs:34:2: 34:2
+          StorageDead(_5);                 // scope 2 at $DIR/invalid_constant.rs:35:56: 35:57
+          StorageLive(_6);                 // scope 3 at $DIR/invalid_constant.rs:39:9: 39:22
+          nop;                             // scope 0 at $DIR/invalid_constant.rs:15:11: 42:2
+          StorageDead(_6);                 // scope 3 at $DIR/invalid_constant.rs:42:1: 42:2
+          StorageDead(_4);                 // scope 2 at $DIR/invalid_constant.rs:42:1: 42:2
+          StorageDead(_2);                 // scope 1 at $DIR/invalid_constant.rs:42:1: 42:2
+          StorageDead(_1);                 // scope 0 at $DIR/invalid_constant.rs:42:1: 42:2
+          return;                          // scope 0 at $DIR/invalid_constant.rs:42:2: 42:2
       }
   }
   

diff --git a/src/test/mir-opt/const_prop/invalid_constant.rs b/src/test/mir-opt/const_prop/invalid_constant.rs
index e0879cf4800caa4219243a89c5f997fd73a26745..492ef404916d49f9f04d62b909e042875357cdc2 100644 (file)
--- a/src/test/mir-opt/const_prop/invalid_constant.rs
+++ b/src/test/mir-opt/const_prop/invalid_constant.rs
@@ -1,6 +1,8 @@
 // Verify that we can pretty print invalid constants.
 
+#![feature(adt_const_params)]
 #![feature(inline_const)]
+#![allow(incomplete_features)]
 
 #[derive(Copy, Clone)]
 #[repr(u32)]
@@ -31,4 +33,10 @@ union NoVariants {
         empty: Empty,
     }
     let _enum_without_variants = [NoVariants { int: 0 }];
+
+    // A non-UTF-8 string slice. Regression test for #75763 and #78520.
+    struct Str<const S: &'static str>;
+    let _non_utf8_str: Str::<{
+        unsafe { std::mem::transmute::<&[u8], &str>(&[0xC0, 0xC1, 0xF5]) }
+    }>;
 }

diff --git a/src/test/ui/const-generics/issues/issue-75763.rs b/src/test/ui/const-generics/issues/issue-75763.rs
deleted file mode 100644 (file)
index 214a04b..0000000
--- a/src/test/ui/const-generics/issues/issue-75763.rs
+++ /dev/null
@@ -1,16 +0,0 @@
-// ignore-test
-// FIXME(const_generics): This test causes an ICE after reverting #76030.
-#![feature(adt_const_params)]
-#![allow(incomplete_features)]
-
-
-struct Bug<const S: &'static str>;
-
-fn main() {
-    let b: Bug::<{
-        unsafe {
-            // FIXME(adt_const_params): Decide on how to deal with invalid values as const params.
-            std::mem::transmute::<&[u8], &str>(&[0xC0, 0xC1, 0xF5])
-        }
-    }>;
-}