[binutils-gdb] Update read1 example in gdb/testsuite/README

[Tom Tromey]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=c70fdc45f60845852f98eae3b8035de1a2df78de

commit c70fdc45f60845852f98eae3b8035de1a2df78de
Author: Tom Tromey <tromey@adacore.com>
Date:   Wed Jun 9 08:34:47 2021 -0600

    Update read1 example in gdb/testsuite/README
    
    Tom de Vries noticed that the recent changes to the testsuite's
    configury required an update to the README.  This patch changes the
    text to document the new reality.
    
    2021-06-09  Tom Tromey  <tromey@adacore.com>
    
            * README (Example): Update read1 example.

Diff:
---
 gdb/testsuite/ChangeLog | 4 ++++
 gdb/testsuite/README    | 6 +++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index d9bda537805..39aa6489df0 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2021-06-09  Tom Tromey  <tromey@adacore.com>
+
+	* README (Example): Update read1 example.
+
 2021-06-09  Simon Marchi  <simon.marchi@polymtl.ca>
 
 	* lib/tuiterm.exp (Term) <_check_box>: Improve logging.
diff --git a/gdb/testsuite/README b/gdb/testsuite/README
index 0036753eff0..862f423a988 100644
--- a/gdb/testsuite/README
+++ b/gdb/testsuite/README
@@ -347,9 +347,13 @@ return at most 1 byte.
 To enable this, either pass a non-empty value in the READ1 make
 variable, or use the check-read1 make target instead of check.
 
-Examples:
+Example:
 
 	make -j10 check-read1 TESTS="*/paginate-*.exp"
+
+If you've already built the read1 support code, either via a previous
+'check-read1' run, or by using "make read1", you can use:
+
 	make -j10 check READ1="1"
 
 Note: While the intention is to detect races and make otherwise passing tests