src/buildall.bash: mention no longer being used by Go build system

The buildall.bash script was initially added in 2015 (in CL 9438),
documented as used in the implementation of the new compile-only
builders at the time.

That description was updated as the builder implementation changed
from "linux-amd64-compilesmoke" to "all-compile" and most recently
to "misc-compile", which it still mentions today.

The build system stopped using it in CL 464955 and there are no plans
to use it again in the future, so update the description so that it's
not misleading. Notably, adding additional checks to this script does
not mean they will be caught by builders.

Updates #31916.
Updates #58163.

Change-Id: I17558b1c150a3ad95105de14511c51791287991b
Reviewed-on: https://go-review.googlesource.com/c/go/+/513755
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/src/buildall.bash b/src/buildall.bash
index 4e9b15bf4b..3b8f6ee6f5 100755
--- a/src/buildall.bash
+++ b/src/buildall.bash
@@ -6,8 +6,12 @@
 # Usage: buildall.bash [-e] [pattern]
 #
 # buildall.bash builds the standard library for all Go-supported
-# architectures. It is used by the "misc-compile" trybot builders,
-# as a smoke test to quickly flag portability issues.
+# architectures.
+#
+# Originally the Go build system used it as a smoke test to quickly
+# flag portability issues in builders named "misc-compile" or "all-compile".
+# As of CL 464955, the build system uses make.bash -compile-only instead,
+# so this script no longer runs in any automated fashion.
 #
 # Options:
 #   -e: stop at first failure