Re: [PATCH] libstdc++: testsuite: use -lbsd for net_ts on RTEMS

[Alexandre Oliva <oliva@adacore.com>]

On Jun 23, 2022, Alexandre Oliva <oliva@adacore.com> wrote:

> Sorry, I goofed when testing this, and another internal xfail machinery
> hid the bug: I had to use dg-xfail-run-if instead.

And then, having enabled pipe(), disabled the internal xfail machinery,
and added -Wl,--gc-sections after -lbsd as recommended, I found that
net/timer/waitable/cons.cc passed; that the other waitable tests failed
to link because of poll(), not pipes; and that the resolver tests failed
for other reasons.

So here's the adjusted patch I'm using now, and that I'll check in
shortly.


libstdc++: xfail experimental/net tests on rtems

Some net/timer/waitable tests fail on rtems because poll() is not
available.

The above, as well as net/internet/resolver/ops tests and
net/timer/waitable/cons.cc, will fail early at runtime unless mkfifo
is enabled in the RTEMS configuration, because the io_context ctor
throws when pipe() fails.

However, even enabling pipes and adjusting the net_ts link command to
use --gc-sections for -lbsd as recommended, both
net/internet/resolver/ops still fail at runtime.

Regstrapped on x86_64-linux-gnu, also tested with a cross to
aarch64-rtems6.  Ok to install?


for  libstdc++-v3/ChangeLog

	* testsuite/lib/dg-options.exp (add_options_for_net_ts):
	Add -Wl,--gc-sections for RTEMS targets.
	* testsuite/experimental/net/timer/waitable/dest.cc: Link-time
	xfail on RTEMS.
	* testsuite/experimental/net/timer/waitable/ops.cc: Likewise.
	* testsuite/experimental/net/internet/resolver/ops/lookup.cc:
	Execution-time xfail on RTEMS.
	* testsuite/experimental/net/internet/resolver/ops/reverse.cc:
	Likewise.
---
 .../net/internet/resolver/ops/lookup.cc            |    1 +
 .../net/internet/resolver/ops/reverse.cc           |    1 +
 .../experimental/net/timer/waitable/dest.cc        |    1 +
 .../experimental/net/timer/waitable/ops.cc         |    1 +
 libstdc++-v3/testsuite/lib/dg-options.exp          |    6 +-----
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/lookup.cc b/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/lookup.cc
index eb411dea8369c..0ac9cb3513d7e 100644
--- a/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/lookup.cc
+++ b/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/lookup.cc
@@ -18,6 +18,7 @@
 // { dg-do run { target c++14 } }
 // { dg-require-effective-target net_ts_ip }
 // { dg-add-options net_ts }
+// { dg-xfail-run-if "io_context requires a working pipe" { *-*-rtems* } }
 
 #include <experimental/internet>
 #include <testsuite_hooks.h>
diff --git a/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/reverse.cc b/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/reverse.cc
index 361df2676efc8..dfdf855c68cd7 100644
--- a/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/reverse.cc
+++ b/libstdc++-v3/testsuite/experimental/net/internet/resolver/ops/reverse.cc
@@ -18,6 +18,7 @@
 // { dg-do run { target c++14 } }
 // { dg-require-effective-target net_ts_ip }
 // { dg-add-options net_ts }
+// { dg-xfail-run-if "io_context requires a working pipe" { *-*-rtems* } }
 
 #include <experimental/internet>
 #include <testsuite_hooks.h>
diff --git a/libstdc++-v3/testsuite/experimental/net/timer/waitable/dest.cc b/libstdc++-v3/testsuite/experimental/net/timer/waitable/dest.cc
index f571f4a8d861a..384f768c2b56d 100644
--- a/libstdc++-v3/testsuite/experimental/net/timer/waitable/dest.cc
+++ b/libstdc++-v3/testsuite/experimental/net/timer/waitable/dest.cc
@@ -17,6 +17,7 @@
 
 // { dg-do run { target c++14 } }
 // { dg-add-options libatomic }
+// { dg-xfail-if "poll not available" { *-*-rtems* } }
 
 #include <experimental/timer>
 #include <testsuite_hooks.h>
diff --git a/libstdc++-v3/testsuite/experimental/net/timer/waitable/ops.cc b/libstdc++-v3/testsuite/experimental/net/timer/waitable/ops.cc
index 97ab629b893a9..815ad71578035 100644
--- a/libstdc++-v3/testsuite/experimental/net/timer/waitable/ops.cc
+++ b/libstdc++-v3/testsuite/experimental/net/timer/waitable/ops.cc
@@ -17,6 +17,7 @@
 
 // { dg-do run { target c++14 } }
 // { dg-add-options libatomic }
+// { dg-xfail-if "poll not available" { *-*-rtems* } }
 
 #include <experimental/timer>
 #include <testsuite_hooks.h>
diff --git a/libstdc++-v3/testsuite/lib/dg-options.exp b/libstdc++-v3/testsuite/lib/dg-options.exp
index b61c4c0cb8fcd..cc312edc172e4 100644
--- a/libstdc++-v3/testsuite/lib/dg-options.exp
+++ b/libstdc++-v3/testsuite/lib/dg-options.exp
@@ -281,11 +281,7 @@ proc add_options_for_net_ts { flags } {
     if { [istarget *-*-solaris2*] } {
 	return "$flags -lsocket -lnsl"
     } elseif { [istarget *-*-rtems*] } {
-	# Adding -Wl,--gc-sections would enable a few more tests to
-	# link, but all of them fail at runtime anyway, because the
-	# io_context ctor calls pipe(), which always fails, and thus
-	# the ctor throws a system error.
-	return "$flags -lbsd"
+	return "$flags -lbsd -Wl,--gc-sections"
     }
     return $flags
 }


-- 
Alexandre Oliva, happy hacker                https://FSFLA.org/blogs/lxo/
   Free Software Activist                       GNU Toolchain Engineer
Disinformation flourishes because many people care deeply about injustice
but very few check the facts.  Ask me about <https://stallmansupport.org>