[PATCH 4/7] Use errno value of first openp failure

[Hannes Domani <ssbssa@yahoo.de>]

Fixes this testsuite fail on Windows:
FAIL: gdb.base/bad-file.exp: directory

If both tries to open the file fail (without and with ".exe"), use the
errno value of the first try.

gdb/ChangeLog:

2020-05-25  Hannes Domani  <ssbssa@yahoo.de>

	* exec.c (exec_file_attach): Use errno value of first openp failure.
---
 gdb/exec.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/gdb/exec.c b/gdb/exec.c
index 14c77495a3..ee13c5e027 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -435,6 +435,7 @@ exec_file_attach (const char *filename, int from_tty)
 #if defined(__GO32__) || defined(_WIN32) || defined(__CYGWIN__)
 	  if (scratch_chan < 0)
 	    {
+	      int first_errno = errno;
 	      char *exename = (char *) alloca (strlen (filename) + 5);
 
 	      strcat (strcpy (exename, filename), ".exe");
@@ -443,6 +444,8 @@ exec_file_attach (const char *filename, int from_tty)
 				    O_RDWR | O_BINARY
 				    : O_RDONLY | O_BINARY,
 				    &scratch_storage);
+	      if (scratch_chan < 0)
+		errno = first_errno;
 	    }
 #endif
 	  if (scratch_chan < 0)
-- 
2.26.2