Strengthen well known check-cfg names and values test

compiler/rustc_session/src/config.rs

@@ -1422,6 +1422,9 @@ impl CheckCfg {
         };
 
         // NOTE: This should be kept in sync with `default_configuration`
+        //
+        // When adding a new config here you should also update
+        // `tests/ui/check-cfg/well-known-values.rs`.
 
         let panic_values = &PanicStrategy::all();
 

tests/ui/check-cfg/compact-values.rs

@@ -8,7 +8,7 @@
 #[cfg(target(os = "linux", arch = "arm"))]
 pub fn expected() {}
 
-#[cfg(target(os = "linux", arch = "X"))]
+#[cfg(target(os = "linux", pointer_width = "X"))]
 //~^ WARNING unexpected `cfg` condition value
 pub fn unexpected() {}
 

tests/ui/check-cfg/compact-values.stderr

@@ -1,10 +1,10 @@
 warning: unexpected `cfg` condition value: `X`
   --> $DIR/compact-values.rs:11:28
    |
-LL | #[cfg(target(os = "linux", arch = "X"))]
-   |                            ^^^^^^^^^^
+LL | #[cfg(target(os = "linux", pointer_width = "X"))]
+   |                            ^^^^^^^^^^^^^^^^^^^
    |
-   = note: expected values for `target_arch` are: `aarch64`, `arm`, `avr`, `bpf`, `csky`, `hexagon`, `loongarch64`, `m68k`, `mips`, `mips32r6`, `mips64`, `mips64r6`, `msp430`, `nvptx64`, `powerpc`, `powerpc64`, `riscv32`, `riscv64`, `s390x`, `sparc`, `sparc64`, `wasm32`, `wasm64`, `x86`, `x86_64`
+   = note: expected values for `target_pointer_width` are: `16`, `32`, `64`
    = note: `#[warn(unexpected_cfgs)]` on by default
 
 warning: 1 warning emitted

tests/ui/check-cfg/values-target-json.rs

@@ -10,10 +10,6 @@
 #[lang = "sized"]
 trait Sized {}
 
-#[cfg(target_os = "linuz")]
-//~^ WARNING unexpected `cfg` condition value
-fn target_os_linux_misspell() {}
-
 #[cfg(target_os = "linux")]
 fn target_os_linux() {}
 

tests/ui/check-cfg/well-known-values.rs

@@ -1,41 +1,104 @@
-// This test check that we lint on non well known values and that we don't lint on well known
-// values
+// This test check that we recognize all the well known config names
+// and that we correctly lint on unexpected values.
+//
+// This test also serve as an "anti-regression" for the well known
+// values since the suggestion shows them.
 //
 // check-pass
 // compile-flags: --check-cfg=cfg() -Z unstable-options
 
-#[cfg(target_os = "linuz")]
+#![feature(cfg_overflow_checks)]
+#![feature(cfg_relocation_model)]
+#![feature(cfg_sanitize)]
+#![feature(cfg_target_abi)]
+#![feature(cfg_target_has_atomic)]
+#![feature(cfg_target_has_atomic_equal_alignment)]
+#![feature(cfg_target_thread_local)]
+
+// This part makes sure that none of the well known names are
+// unexpected.
+//
+// BUT to make sure that no expected values changes without
+// being noticed we pass them a obviously wrong value so the
+// diagnostic prints the list of expected values.
+#[cfg(any(
+    // tidy-alphabetical-start
+    debug_assertions = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    doc = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    doctest = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    miri = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    overflow_checks = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    panic = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    proc_macro = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    relocation_model = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    sanitize = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_abi = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_arch = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_endian = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_env = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_family = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_feature = "_UNEXPECTED_VALUE", // currently *any* values are "expected"
+    target_has_atomic = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_has_atomic_equal_alignment = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_has_atomic_load_store = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_os = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_pointer_width = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_thread_local = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    target_vendor = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    test = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    unix = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    windows = "_UNEXPECTED_VALUE",
+    //~^ WARN unexpected `cfg` condition value
+    // tidy-alphabetical-end
+))]
+fn unexpected_values() {}
+
+#[cfg(target_os = "linuz")] // testing that we suggest `linux`
 //~^ WARNING unexpected `cfg` condition value
 fn target_os_linux_misspell() {}
 
+// The #[cfg]s below serve as a safeguard to make sure we
+// don't lint when using an expected well-known name and
+// value, only a small subset of all possible expected
+// configs are tested, since we already test the names
+// above and don't need to test all values, just different
+// combinations (without value, with value, both...).
+
 #[cfg(target_os = "linux")]
 fn target_os_linux() {}
 
-#[cfg(target_has_atomic = "0")]
-//~^ WARNING unexpected `cfg` condition value
-fn target_has_atomic_invalid() {}
-
 #[cfg(target_has_atomic = "8")]
-fn target_has_atomic() {}
+fn target_has_atomic_8() {}
 
-#[cfg(unix = "aa")]
-//~^ WARNING unexpected `cfg` condition value
-fn unix_with_value() {}
+#[cfg(target_has_atomic)]
+fn target_has_atomic() {}
 
 #[cfg(unix)]
 fn unix() {}
 
-#[cfg(miri = "miri")]
-//~^ WARNING unexpected `cfg` condition value
-fn miri_with_value() {}
-
-#[cfg(miri)]
-fn miri() {}
-
-#[cfg(doc = "linux")]
-//~^ WARNING unexpected `cfg` condition value
-fn doc_with_value() {}
-
 #[cfg(doc)]
 fn doc() {}