Rollup merge of #146435 - Kobzol:gcc-download-default-true, r=GuillaumeGomez

Change the default value of `gcc.download-ci-gcc` to `true`

It makes sense for the vast majority of uses (https://github.com/rust-lang/rustc-dev-guide/pull/2587#discussion_r2337374719).

r? ```@GuillaumeGomez```

3 files changed, 10 insertions, 1 deletions

diff --git a/src/bootstrap/defaults/bootstrap.dist.toml b/src/bootstrap/defaults/bootstrap.dist.toml
index 9daf9faac14..b111a20f8d8 100644
--- a/src/bootstrap/defaults/bootstrap.dist.toml
+++ b/src/bootstrap/defaults/bootstrap.dist.toml
@@ -14,6 +14,10 @@ compiletest-use-stage0-libtest = false
 [llvm]
 download-ci-llvm = false
 
+# Most users installing from source want to build all parts of the project from source.
+[gcc]
+download-ci-gcc = false
+
 [rust]
 # We have several defaults in bootstrap that depend on whether the channel is `dev` (e.g. `omit-git-hash` and `download-ci-llvm`).
 # Make sure they don't get set when installing from source.
diff --git a/src/bootstrap/src/core/config/mod.rs b/src/bootstrap/src/core/config/mod.rs
index 5999348a7fe..05a5dfc0bc5 100644
--- a/src/bootstrap/src/core/config/mod.rs
+++ b/src/bootstrap/src/core/config/mod.rs
@@ -422,10 +422,10 @@ impl std::str::FromStr for RustcLto {
 #[derive(Default, Clone)]
 pub enum GccCiMode {
     /// Build GCC from the local `src/gcc` submodule.
-    #[default]
     BuildLocally,
     /// Try to download GCC from CI.
     /// If it is not available on CI, it will be built locally instead.
+    #[default]
     DownloadFromCi,
 }
 
diff --git a/src/bootstrap/src/utils/change_tracker.rs b/src/bootstrap/src/utils/change_tracker.rs
index 01309072927..03b39882e30 100644
--- a/src/bootstrap/src/utils/change_tracker.rs
+++ b/src/bootstrap/src/utils/change_tracker.rs
@@ -541,4 +541,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Info,
         summary: "Added a new option `rust.break-on-ice` to control if internal compiler errors cause a debug break on Windows.",
     },
+    ChangeInfo {
+        change_id: 146435,
+        severity: ChangeSeverity::Info,
+        summary: "The default value of the `gcc.download-ci-gcc` option has been changed to `true`.",
+    },
 ];