From c85f68c4e952294304e5938acb601e66f5df71a0 Mon Sep 17 00:00:00 2001
From: Paul Smith <psmith@gnu.org>
Date: Sat, 18 Feb 2023 13:20:00 -0500
Subject: [PATCH] Allow jobserver style to be forced to "pipe"

Some systems that support mkfifo() don't support the usage that GNU
make wants.  Provide a way to force using "pipe" jobserver mode even
when mkfifo() is available.

* src/makeint.h (MK_OS_HURD): Define if we're on Hurd.
(JOBSERVER_USE_FIFO): Define if we have mkfifo() and we're NOT on
Hurd.
* src/main.c (main): Test JOBSERVER_USE_FIFO not HAVE_MKFIFO.
* src/posixos.c (jobserver_setup): Ditto.
* maintMakefile: Create a config check test for forcing "pipe" mode.
* tests/run_make_tests.pl: Show discovered FEATURES in verbose mode.
---
 maintMakefile           |  2 ++
 src/main.c              |  3 ++-
 src/makeint.h           | 11 +++++++++++
 src/posixos.c           |  4 ++--
 tests/run_make_tests.pl |  1 +
 5 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/maintMakefile b/maintMakefile
index 2747aad6..ae25ee75 100644
--- a/maintMakefile
+++ b/maintMakefile
@@ -274,6 +274,7 @@ CFGCHECK_MAKEFLAGS   = # CFLAGS='$(AM_CFLAGS)'
 checkcfg.strict-c90:  CFGCHECK_CONFIGFLAGS = CFLAGS='-std=c90 -pedantic'
 checkcfg.strict-c90:  CFGCHECK_MAKEFLAGS   =
 
+checkcfg.job-pipe:    CFGCHECK_CONFIGFLAGS = CPPFLAGS=-DJOBSERVER_USE_FIFO=0
 checkcfg.no-jobserver:CFGCHECK_CONFIGFLAGS = --disable-job-server
 checkcfg.no-load:     CFGCHECK_CONFIGFLAGS = --disable-load
 checkcfg.no-guile:    CFGCHECK_CONFIGFLAGS = --without-guile
@@ -289,6 +290,7 @@ checkcfg.no-archives: CFGCHECK_CONFIGFLAGS = CPPFLAGS=-DNO_ARCHIVES
 
 CONFIG_CHECKS := \
 	checkcfg.strict-c90 \
+	checkcfg.job-pipe \
 	checkcfg.no-jobserver \
 	checkcfg.no-load \
 	checkcfg.no-guile \
diff --git a/src/main.c b/src/main.c
index 8ad750b8..dde0d77d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -234,6 +234,7 @@ static const int inf_jobs = 0;
 char *jobserver_auth = NULL;
 
 /* Style for the jobserver.  */
+
 static char *jobserver_style = NULL;
 
 /* Shuffle mode for goals and prerequisites.  */
@@ -1447,7 +1448,7 @@ main (int argc, char **argv, char **envp)
 #endif
 #ifdef MAKE_JOBSERVER
                            " jobserver"
-# ifdef HAVE_MKFIFO
+# if JOBSERVER_USE_FIFO
                            " jobserver-fifo"
 # endif
 #endif
diff --git a/src/makeint.h b/src/makeint.h
index 187974e4..1e1596d2 100644
--- a/src/makeint.h
+++ b/src/makeint.h
@@ -83,6 +83,9 @@ extern int errno;
 #endif
 
 /* Define macros specifying which OS we are building for.  */
+#if __gnu_hurd__
+# define MK_OS_HURD 1
+#endif
 #if defined(__MVS__)
 # define MK_OS_ZOS 1
 #endif
@@ -742,6 +745,14 @@ extern char cmd_prefix;
 
 extern unsigned int no_intermediates;
 
+#if HAVE_MKFIFO
+# if !defined(JOBSERVER_USE_FIFO) && !MK_OS_HURD
+/* It seems that mkfifo() is not working correctly, or at least not the way
+   GNU make wants it to work, on GNU/Hurd so don't use it there.  */
+#  define JOBSERVER_USE_FIFO 1
+# endif
+#endif
+
 #define JOBSERVER_AUTH_OPT      "jobserver-auth"
 
 extern char *jobserver_auth;
diff --git a/src/posixos.c b/src/posixos.c
index 0fe0948a..0cc0a585 100644
--- a/src/posixos.c
+++ b/src/posixos.c
@@ -147,8 +147,8 @@ jobserver_setup (int slots, const char *style)
 {
   int r;
 
-#if HAVE_MKFIFO
-  if (style == NULL || strcmp (style, "fifo") == 0)
+#if JOBSERVER_USE_FIFO
+  if (!style || strcmp (style, "fifo") == 0)
     {
   /* Unfortunately glibc warns about uses of mktemp even though we aren't
      using it in dangerous way here.  So avoid this by generating our own
diff --git a/tests/run_make_tests.pl b/tests/run_make_tests.pl
index a5d9b807..012bd66d 100644
--- a/tests/run_make_tests.pl
+++ b/tests/run_make_tests.pl
@@ -671,6 +671,7 @@ sub set_more_defaults
 
   create_file('features.mk', 'all:;$(info $(.FEATURES))');
   %FEATURES = map { $_ => 1 } split /\s+/, `$make_path -sf features.mk`;
+  print "$make_path FEATURES: @{[%FEATURES]}\n" if $verbose;
   unlink('features.mk');
 
   # Find the default values for different built-in variables