fix circular dependency on cc-rs using a temporary patched version of cc-rs

Author: max-niederman

src/bootstrap/Cargo.lock

@@ -88,8 +88,7 @@ dependencies = [
 [[package]]
 name = "cc"
 version = "1.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1aeb932158bd710538c73702db6945cb68a8fb08c519e6e12706b94263b36db8"
+source = "git+https://github.com/rust-lang/cc-rs?rev=6fe995c675dc1178f570752fa8f6de82913a91dc#6fe995c675dc1178f570752fa8f6de82913a91dc"
 dependencies = [
  "shlex",
 ]

src/bootstrap/Cargo.toml

@@ -96,3 +96,7 @@ debug = 0
 [profile.dev.package]
 # Only use debuginfo=1 to further reduce compile times.
 bootstrap.debug = 1
+
+[patch.crates-io]
+# FIXME: remove this once the `armv7a-vex-v5` target is available on nightly and cc-rs is updated with it
+cc = { git = "https://github.com/rust-lang/cc-rs", rev = "6fe995c675dc1178f570752fa8f6de82913a91dc" }

src/tools/tidy/src/extdeps.rs

@@ -8,6 +8,8 @@ const ALLOWED_SOURCES: &[&str] = &[
     r#""registry+https://github.com/rust-lang/crates.io-index""#,
     // This is `rust_team_data` used by `site` in src/tools/rustc-perf,
     r#""git+https://github.com/rust-lang/team#a5260e76d3aa894c64c56e6ddc8545b9a98043ec""#,
+    // This is temporarily used to bootstrap the `armv7a_vex_v5` target until cc-rs has it in its generated target list.
+    r#""git+https://github.com/rust-lang/cc-rs?rev=6fe995c675dc1178f570752fa8f6de82913a91dc#6fe995c675dc1178f570752fa8f6de82913a91dc""#,
 ];
 
 /// Checks for external package sources. `root` is the path to the directory that contains the