Rollup merge of #82255 - nhwn:nonzero-err-as-bug, r=davidtwco

Make `treat_err_as_bug` Option<NonZeroUsize>

`rustc -Z treat-err-as-bug=N` already requires `N` to be nonzero when the argument is parsed, so changing the type from `Option<usize>` to `Option<NonZeroUsize>` is a low-hanging fruit in terms of layout optimization.

2 files changed, 7 insertions, 4 deletions

diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index 4533b37f10b..e4f7e140281 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -2313,6 +2313,7 @@ crate mod dep_tracking {
     use std::collections::hash_map::DefaultHasher;
     use std::collections::BTreeMap;
     use std::hash::Hash;
+    use std::num::NonZeroUsize;
     use std::path::PathBuf;
 
     pub trait DepTrackingHash {
@@ -2353,6 +2354,7 @@ crate mod dep_tracking {
     impl_dep_tracking_hash_via_hash!(lint::Level);
     impl_dep_tracking_hash_via_hash!(Option<bool>);
     impl_dep_tracking_hash_via_hash!(Option<usize>);
+    impl_dep_tracking_hash_via_hash!(Option<NonZeroUsize>);
     impl_dep_tracking_hash_via_hash!(Option<String>);
     impl_dep_tracking_hash_via_hash!(Option<(String, u64)>);
     impl_dep_tracking_hash_via_hash!(Option<Vec<String>>);
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index baa0502521d..d439753d042 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -16,6 +16,7 @@ use std::collections::BTreeMap;
 
 use std::collections::hash_map::DefaultHasher;
 use std::hash::Hasher;
+use std::num::NonZeroUsize;
 use std::path::PathBuf;
 use std::str;
 
@@ -591,10 +592,10 @@ macro_rules! options {
             true
         }
 
-        fn parse_treat_err_as_bug(slot: &mut Option<usize>, v: Option<&str>) -> bool {
+        fn parse_treat_err_as_bug(slot: &mut Option<NonZeroUsize>, v: Option<&str>) -> bool {
             match v {
-                Some(s) => { *slot = s.parse().ok().filter(|&x| x != 0); slot.unwrap_or(0) != 0 }
-                None => { *slot = Some(1); true }
+                Some(s) => { *slot = s.parse().ok(); slot.is_some() }
+                None => { *slot = NonZeroUsize::new(1); true }
             }
         }
 
@@ -1141,7 +1142,7 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
         "for every macro invocation, print its name and arguments (default: no)"),
     trap_unreachable: Option<bool> = (None, parse_opt_bool, [TRACKED],
         "generate trap instructions for unreachable intrinsics (default: use target setting, usually yes)"),
-    treat_err_as_bug: Option<usize> = (None, parse_treat_err_as_bug, [TRACKED],
+    treat_err_as_bug: Option<NonZeroUsize> = (None, parse_treat_err_as_bug, [TRACKED],
         "treat error number `val` that occurs as bug"),
     trim_diagnostic_paths: bool = (true, parse_bool, [UNTRACKED],
         "in diagnostics, use heuristics to shorten paths referring to items"),