denote which algorithms cargo supports

Author: Xaeroxe

Cargo.lock

@@ -2227,7 +2227,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0c2a198fb6b0eada2a8df47933734e6d35d350665a33a3593d7164fa52c75c19"
 dependencies = [
  "cfg-if",
- "windows-targets 0.48.5",
+ "windows-targets 0.52.5",
 ]
 
 [[package]]

compiler/rustc_session/src/options.rs

@@ -412,7 +412,8 @@ mod desc {
     pub const parse_merge_functions: &str = "one of: `disabled`, `trampolines`, or `aliases`";
     pub const parse_symbol_mangling_version: &str =
         "one of: `legacy`, `v0` (RFC 2603), or `hashed`";
-    pub const parse_src_file_hash: &str = "either `md5`, `sha1`, or `sha256`";
+    pub const parse_cargo_src_file_hash: &str = "one of `sha256`";
+    pub const parse_src_file_hash: &str = "one of `md5`, `sha1`, or `sha256`";
     pub const parse_relocation_model: &str =
         "one of supported relocation models (`rustc --print relocation-models`)";
     pub const parse_code_model: &str = "one of supported code models (`rustc --print code-models`)";
@@ -1222,6 +1223,23 @@ mod parse {
         true
     }
 
+    pub(crate) fn parse_cargo_src_file_hash(
+        slot: &mut Option<SourceFileHashAlgorithm>,
+        v: Option<&str>,
+    ) -> bool {
+        match v.and_then(|s| SourceFileHashAlgorithm::from_str(s).ok()) {
+            Some(hash_kind) => {
+                if hash_kind.supported_in_cargo() {
+                    *slot = Some(hash_kind);
+                } else {
+                    return false;
+                }
+            }
+            _ => return false,
+        }
+        true
+    }
+
     pub(crate) fn parse_target_feature(slot: &mut String, v: Option<&str>) -> bool {
         match v {
             Some(s) => {
@@ -1609,8 +1627,8 @@ options! {
         "instrument control-flow architecture protection"),
     check_cfg_all_expected: bool = (false, parse_bool, [UNTRACKED],
         "show all expected values in check-cfg diagnostics (default: no)"),
-    checksum_hash_algorithm: Option<SourceFileHashAlgorithm> = (None, parse_src_file_hash, [TRACKED],
-        "hash algorithm of source files used to check freshness in cargo (`md5`, `sha1`, or `sha256`)"),
+    checksum_hash_algorithm: Option<SourceFileHashAlgorithm> = (None, parse_cargo_src_file_hash, [TRACKED],
+        "hash algorithm of source files used to check freshness in cargo (`sha256`)"),
     codegen_backend: Option<String> = (None, parse_opt_string, [TRACKED],
         "the backend to use"),
     combine_cgu: bool = (false, parse_bool, [TRACKED],

compiler/rustc_span/src/lib.rs

@@ -1460,12 +1460,21 @@ pub enum SourceFileHashAlgorithm {
     Sha256,
 }
 
+impl SourceFileHashAlgorithm {
+    pub fn supported_in_cargo(&self) -> bool {
+        match self {
+            Self::Md5 | Self::Sha1 => false,
+            Self::Sha256 => true,
+        }
+    }
+}
+
 impl Display for SourceFileHashAlgorithm {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.write_str(match self {
-            SourceFileHashAlgorithm::Md5 => "md5",
-            SourceFileHashAlgorithm::Sha1 => "sha1",
-            SourceFileHashAlgorithm::Sha256 => "sha256",
+            Self::Md5 => "md5",
+            Self::Sha1 => "sha1",
+            Self::Sha256 => "sha256",
         })
     }
 }