[PATCH] [testsuite] Fix pretty printers regexps for GDB output

[Christophe Lyon]

GDB emits end of lines as \r\n, we currently match the reverse \n\r,
possibly leading to mismatches under racy conditions.

I noticed this while running the GCC testsuite using the equivalent of
GDB's READ1 feature [1] which helps detecting bufferization issues.

Adjusting the first regexp to match the right order implied fixing the
second one, to skip the empty lines.

Tested on aarch64-linux-gnu.

[1] https//github.com/bminor/binutils-gdb/blob/master/gdb/testsuite/README#L269

2024-01-24  Christophe Lyon  <christophe.l...@linaro.org>

        libstdc++-v3/
        * testsuite/lib/gdb-test.exp (gdb-test): Fix regexps.
---
 libstdc++-v3/testsuite/lib/gdb-test.exp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libstdc++-v3/testsuite/lib/gdb-test.exp 
b/libstdc++-v3/testsuite/lib/gdb-test.exp
index 31206f2fc32..0de8d9ee153 100644
--- a/libstdc++-v3/testsuite/lib/gdb-test.exp
+++ b/libstdc++-v3/testsuite/lib/gdb-test.exp
@@ -194,7 +194,7 @@ proc gdb-test { marker {selector {}} {load_xmethods 0} } {
 
     set test_counter 0
     remote_expect target [timeout_value] {
-       -re {^(type|\$([0-9]+)) = ([^\n\r]*)[\n\r]+} {
+       -re {^(type|\$([0-9]+)) = ([^\n\r]*)\r\n} {
            send_log "got: $expect_out(buffer)"
 
            incr test_counter
@@ -250,7 +250,7 @@ proc gdb-test { marker {selector {}} {load_xmethods 0} } {
            return
        }
 
-       -re {^[^$][^\n\r]*[\n\r]+} {
+       -re {^[\r\n]*[^$][^\n\r]*\r\n} {
            send_log "skipping: $expect_out(buffer)"
            exp_continue
        }
-- 
2.34.1