Auto merge of #150912 - matthiaskrgr:rollup-SHXgjYS, r=matthiaskrgr

Rollup of 11 pull requests

Successful merges:

 - rust-lang/rust#150269 (Remove inactive nvptx maintainer)
 - rust-lang/rust#150713 (mgca: Type-check fields of struct expr const args)
 - rust-lang/rust#150765 (rustc_parse_format: improve error for missing `:` before `?` in format args)
 - rust-lang/rust#150847 (Fix broken documentation links to SipHash)
 - rust-lang/rust#150867 (rustdoc_json: Remove one call to `std::mem::take` in `after_krate`)
 - rust-lang/rust#150872 (Fix some loop block coercion diagnostics)
 - rust-lang/rust#150874 (Ignore `rustc-src-gpl` in fast try builds)
 - rust-lang/rust#150875 (Refactor artifact keep mode in bootstrap)
 - rust-lang/rust#150876 (Mention that `rustc_codegen_gcc` is a subtree in `rustc-dev-guide`)
 - rust-lang/rust#150882 (Supress unused_parens lint for guard patterns)
 - rust-lang/rust#150884 (Update bors email in CI postprocessing step)

Failed merges:

 - rust-lang/rust#150869 (Emit error instead of delayed bug when meeting mismatch type for const tuple)

r? @ghost

Author: rust-bors[bot]

src/external-repos.md

@@ -22,6 +22,7 @@ The following external projects are managed using some form of a `subtree`:
 * [rustfmt](https://github.com/rust-lang/rustfmt)
 * [rust-analyzer](https://github.com/rust-lang/rust-analyzer)
 * [rustc_codegen_cranelift](https://github.com/rust-lang/rustc_codegen_cranelift)
+* [rustc_codegen_gcc](https://github.com/rust-lang/rustc_codegen_gcc)
 * [rustc-dev-guide](https://github.com/rust-lang/rustc-dev-guide)
 * [compiler-builtins](https://github.com/rust-lang/compiler-builtins)
 * [stdarch](https://github.com/rust-lang/stdarch)
@@ -40,6 +41,7 @@ implement a new tool feature or test, that should happen in one collective rustc
     * `portable-simd` ([sync script](https://github.com/rust-lang/portable-simd/blob/master/subtree-sync.sh))
     * `rustfmt`
     * `rustc_codegen_cranelift` ([sync script](https://github.com/rust-lang/rustc_codegen_cranelift/blob/113af154d459e41b3dc2c5d7d878e3d3a8f33c69/scripts/rustup.sh#L7))
+    * `rustc_codegen_gcc` ([sync guide](https://github.com/rust-lang/rustc_codegen_gcc/blob/master/doc/subtree.md))
 * Using the [josh](#synchronizing-a-josh-subtree) tool
     * `miri`
     * `rust-analyzer`