Unconditionally enable PGRP_PIPE on Linux (the kernel), regardless of
the kernel version in use on the build machine.

diff -purN bash-5.0-orig/configure bash-5.0/configure
--- configure	1970-01-01 01:00:00.000000000 +0100
+++ configure	2019-09-29 11:51:42.664518665 +0200
@@ -16312,11 +16312,7 @@ solaris2.10*)	LOCAL_CFLAGS=-DSOLARIS  ;;
 solaris2*)	LOCAL_CFLAGS=-DSOLARIS ;;
 lynxos*)	LOCAL_CFLAGS=-DRECYCLES_PIDS ;;
 linux*)		LOCAL_LDFLAGS=-rdynamic		 # allow dynamic loading
-		case "`uname -r`" in
-		1.*|2.[0123]*)	: ;;
-		*)	$as_echo "#define PGRP_PIPE 1" >>confdefs.h
- ;;
-		esac ;;
+		$as_echo "#define PGRP_PIPE 1" >>confdefs.h ;;
 netbsd*|openbsd*)	LOCAL_CFLAGS="-DDEV_FD_STAT_BROKEN" ;;
 *qnx[67]*)	LOCAL_LIBS="-lncurses" ;;
 *qnx*)		LOCAL_CFLAGS="-Dqnx -F -3s" LOCAL_LDFLAGS="-3s" LOCAL_LIBS="-lunix -lncurses" ;;
diff -purN bash-5.0-orig/configure.ac bash-5.0/configure.ac
--- configure.ac	1970-01-01 01:00:00.000000000 +0100
+++ configure.ac	2019-09-29 11:51:10.692026225 +0200
@@ -1108,10 +1108,7 @@ solaris2.10*)	LOCAL_CFLAGS=-DSOLARIS  ;;
 solaris2*)	LOCAL_CFLAGS=-DSOLARIS ;;
 lynxos*)	LOCAL_CFLAGS=-DRECYCLES_PIDS ;;
 linux*)		LOCAL_LDFLAGS=-rdynamic		 # allow dynamic loading
-		case "`uname -r`" in
-		1.*|2.[[0123]]*)	: ;;
-		*)	AC_DEFINE(PGRP_PIPE) ;;
-		esac ;;
+		AC_DEFINE(PGRP_PIPE) ;;
 netbsd*|openbsd*)	LOCAL_CFLAGS="-DDEV_FD_STAT_BROKEN" ;;
 *qnx[[67]]*)	LOCAL_LIBS="-lncurses" ;;
 *qnx*)		LOCAL_CFLAGS="-Dqnx -F -3s" LOCAL_LDFLAGS="-3s" LOCAL_LIBS="-lunix -lncurses" ;;
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<tr><td><span title='2022-07-12 01:17:45 +0200'>2022-07-12</span></td><td><a href='/guix/commit/gnu/packages/patches/llvm-3.x.1-fix-build-with-gcc.patch?id=3485984a090edd5b1721a69a389a2e44077354e7'>gnu: llvm-3.7, llvm-3.8: Fix build with gcc.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/patches/clang-runtime-3.7-fix-build-with-python3.patch,
gnu/packages/patches/llvm-3.x.1-fix-build-with-gcc.patch: New files.
* gnu/packages/llvm.scm (clang-runtime-3.7, llvm-3.7, llvm-3.8): Use patches.
* gnu/local.mk: Register patches.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Greg Hogan</td></tr>