Inline sanitizer flag selection now that it's infallible

src/project.rs

@@ -1,5 +1,5 @@
 use crate::options::{self, BuildMode, BuildOptions, Sanitizer};
-use crate::rustc_version::{is_nightly, rust_version_string, sanitizer_flag, RustVersion};
+use crate::rustc_version::{is_nightly, rust_version_string, RustVersion};
 use crate::utils::default_target;
 use anyhow::{anyhow, bail, Context, Result};
 use cargo_metadata::MetadataCommand;
@@ -195,7 +195,10 @@ impl FuzzProject {
             let rust_version_string = rust_version_string()?;
             let rust_version =
                 RustVersion::from_str(&rust_version_string).map_err(|e| anyhow::anyhow!(e))?;
-            let sanitizer_flag = sanitizer_flag(&rust_version)?;
+            let sanitizer_flag = match rust_version.has_sanitizers_on_stable() {
+                true => "-Csanitizer",
+                false => "-Zsanitizer",
+            };
 
             // Set rustc CLI arguments for the chosen sanitizer
             match build.sanitizer {

src/rustc_version.rs

@@ -22,18 +22,6 @@ pub fn rust_version_string() -> anyhow::Result<String> {
     String::from_utf8(raw_output).context("`rustc --version` returned non-text output somehow")
 }
 
-/// Returns either "-Zsanitizer" or "-Csanitizer" depending on the compiler version.
-///
-/// Stabilization of sanitizers has removed the "-Zsanitizer" flag, even on nightly,
-/// so we have to choose the appropriate flag for the compiler version.
-/// More info: <https://github.com/rust-lang/rust/pull/123617>
-pub fn sanitizer_flag(version: &RustVersion) -> anyhow::Result<&'static str> {
-    match version.has_sanitizers_on_stable() {
-        true => Ok("-Csanitizer"),
-        false => Ok("-Zsanitizer"),
-    }
-}
-
 #[derive(Debug, Copy, Clone, Eq, PartialEq, PartialOrd)]
 pub struct RustVersion {
     pub major: u32,