https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108261
--- Comment #26 from Iain Sandoe <iains at gcc dot gnu.org> ---
(In reply to Gaius Mulley from comment #25)
> Created attachment 54516 [details]
> Proposed fix version 6
>
> Version 6 (more coroutine tests) and RTint.mod with more descriptive
> variable names.
This does not solve the timeout issues on Darwin (mentioned here because we
were wondering if the issue was related to init ordering).
-----
Here's a patch that seems to prevent the hangs (but at the expense of a lot of
diagnostic output - it seems modula-2 is somehow calling the OS select with
some bad input) .. I cannot reproduce this calling it from C.
>From 92cc7b7c19735ea32e0800b369a2e49f85047e27 Mon Sep 17 00:00:00 2001
From: Iain Sandoe <i...@sandoe.co.uk>
Date: Thu, 23 Feb 2023 09:54:01 +0000
Subject: [PATCH] modula-2 : Some TLC for select fail case diagnostics
---
gcc/m2/gm2-libs/RTint.mod | 52 ++++++++++++++++++++++++++-------------
1 file changed, 35 insertions(+), 17 deletions(-)
diff --git a/gcc/m2/gm2-libs/RTint.mod b/gcc/m2/gm2-libs/RTint.mod
index d8ca8dd5694..796430a55df 100644
--- a/gcc/m2/gm2-libs/RTint.mod
+++ b/gcc/m2/gm2-libs/RTint.mod
@@ -669,6 +669,7 @@ PROCEDURE Listen (untilInterrupt: BOOLEAN;
VAR
found: BOOLEAN ;
r : INTEGER ;
+ zero,
after,
b4,
t : Timeval ;
@@ -742,6 +743,7 @@ BEGIN
ELSE
GetTime (t, s, m) ;
Assert (m<Microseconds) ;
+ zero := InitTime (0, 0) ;
b4 := InitTime (0, 0) ;
after := InitTime (0, 0) ;
r := GetTimeOfDay (b4) ;
@@ -762,23 +764,35 @@ BEGIN
IF r=-1
THEN
perror ("select") ;
- r := select (maxFd+1, i, o, NIL, NIL) ;
- IF r=-1
+ r := select (maxFd+1, i, o, NIL, zero) ;
+ IF r#-1
THEN
- perror ("select timeout argument is faulty")
- END ;
- r := select (maxFd+1, i, NIL, NIL, t) ;
- IF r=-1
- THEN
- perror ("select output fd argument is faulty")
- END ;
- r := select (maxFd+1, NIL, o, NIL, t) ;
- IF r=-1
- THEN
- perror ("select input fd argument is faulty")
+ perror ("select timeout argument was faulty")
ELSE
- perror ("select maxFD+1 argument is faulty")
- END
+ r := select (maxFd+1, i, NIL, NIL, t) ;
+ IF r#-1
+ THEN
+ perror ("select output fd argument was faulty")
+ ELSE
+ r := select (maxFd+1, NIL, o, NIL, t) ;
+ IF r#-1
+ THEN
+ perror ("select input fd argument was faulty")
+ ELSE
+ IF maxFd=-1
+ THEN
+ r := select (0, NIL, NIL, NIL, t) ;
+ IF r=-1
+ THEN
+ perror ("select does not accept nfds == 0 ") ;
+ r := 0
+ END
+ ELSE
+ perror ("select maxFD+1 argument was faulty") ;
+ END
+ END
+ END
+ END
END
UNTIL r#-1
END ;
@@ -791,11 +805,15 @@ BEGIN
END ;
IF after#NIL
THEN
- t := KillTime (after)
+ after := KillTime (after)
END ;
IF b4#NIL
THEN
- t := KillTime (b4)
+ b4 := KillTime (b4)
+ END ;
+ IF zero#NIL
+ THEN
+ zero := KillTime (zero)
END ;
IF i#NIL
THEN
--
2.24.3 (Apple Git-128)
