[binutils-gdb] gdb/testsuite: make gdb_test_multiple return immediately if send_gdb fails

[binutils-gdb] gdb/testsuite: make gdb_test_multiple return immediately if send_gdb fails

[Simon Marchi]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=d56614a9925791b15d7052eb4c798ab24a724611

commit d56614a9925791b15d7052eb4c798ab24a724611
Author: Simon Marchi <simon.marchi@polymtl.ca>
Date:   Mon Nov 21 09:41:08 2022 -0500

    gdb/testsuite: make gdb_test_multiple return immediately if send_gdb fails
    
    In the failure seen by Philippe here:
    
      https://inbox.sourceware.org/gdb-patches/20221120173024.3647464-1-philippe.waroquiers@skynet.be/
    
    ... the testsuite only outputs PASSes, and an ERROR, resulting from an
    uncaught exception.  This is a bit sneaky, because ERRORs are not
    reported in the test summary.  In certain circumstances, it can be easy
    to miss.
    
    Normally, gdb_test_multiple outputs an UNRESOLVED when GDB crashes.  But
    this is only if it manages to send the command, and it's that command
    that crashes GDB.  Here, the ERROR is due to the fact that GDB had
    already crashed by the time we entered gdb_test_multiple and tried to
    send a command.  GDB was crashed by the previous "file" command, sent by
    gdb_unload.  Because gdb_unload uses bare expect, it didn't record a
    test failure when crashing GDB (this will be addressed separately).
    
    In this patch, I propose to make gdb_test_multiple call unresolved
    directly and return -1 send_gdb fails.  This way, if GDB is already
    crashed by the time we enter gdb_test_multiple, it will leave a trace in
    the test results in the form of an UNRESOLVED.  It will also spare us
    the not-so-useful-in-my-opinion TCL backtrace.
    
    Before, it looks like:
    
        ERROR: Couldn't send python print(objfile.filename) to GDB.
        ERROR: : spawn id exp9 not open
            while executing
        "expect {
        -i exp9 -timeout 10
                -re ".*A problem internal to GDB has been detected" {
                    fail "$message (GDB internal error)"
                    gdb_internal_error..."
            ("uplevel" body line 1)
            invoked from within
        "uplevel $body" NONE : spawn id exp9 not open
    
    And after:
    
        Couldn't send python print(objfile.filename) to GDB.
        UNRESOLVED: gdb.python/py-objfile.exp: objfile.filename after objfile is unloaded
    
    Change-Id: I72af8dc0d687826fc3f76911c27a9e5f91b677ba
    Approved-By: Tom de Vries <tdevries@suse.de>

Diff:
---
 gdb/testsuite/lib/gdb.exp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index b4d4e46d492..e193a20768c 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -1161,7 +1161,9 @@ proc gdb_test_multiple { command message args } {
 	    if { $foo < [expr $len - 1] } {
 		set str [string range "$string" 0 $foo]
 		if { [send_gdb "$str"] != "" } {
-		    perror "Couldn't send $command to GDB."
+		    verbose -log "Couldn't send $command to GDB."
+		    unresolved $message
+		    return -1
 		}
 		# since we're checking if each line of the multi-line
 		# command are 'accepted' by GDB here,
@@ -1180,7 +1182,9 @@ proc gdb_test_multiple { command message args } {
 	}
 	if { "$string" != "" } {
 	    if { [send_gdb "$string"] != "" } {
-		perror "Couldn't send $command to GDB."
+		verbose -log "Couldn't send $command to GDB."
+		unresolved $message
+		return -1
 	    }
 	}
     }