Fix RISC-V vfork build with Linux 5.3 kernel headers.

Building glibc for RISC-V with Linux 5.3 kernel headers fails because
<linux/sched.h>, included in vfork.S for CLONE_* constants, contains a
structure definition not safe for inclusion in assembly code.

All other architectures already avoid use of that header in vfork.S,
either defining the CLONE_* constants locally or embedding the
required values directly in the relevant instruction, where they
implement vfork using the clone syscall (see the implementations for
aarch64, ia64, mips and nios2).  This patch makes the RISC-V version
define the constants locally like the other architectures.

Tested build for all three RISC-V configurations in
build-many-glibcs.py with Linux 5.3 headers.

	* sysdeps/unix/sysv/linux/riscv/vfork.S: Do not include
	<linux/sched.h>.
	(CLONE_VM): New macro.
	(CLONE_VFORK): Likewise.

(cherry picked from commit 8cacbcf4a984ccac24efedb795d9c8a7f149d17b)

diff --git a/ChangeLog b/ChangeLog
index 1061c8c796f74a99bea81280e55e3538bb6b05c0..74f7923696e5215586c7aec6341ea20e4fdb5823 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2019-09-20  Joseph Myers  <joseph@codesourcery.com>
+
+       * sysdeps/unix/sysv/linux/riscv/vfork.S: Do not include
+       <linux/sched.h>.
+       (CLONE_VM): New macro.
+       (CLONE_VFORK): Likewise.
+
 2019-09-14  Aurelien Jarno  <aurelien@aurel32.net>
 
        [BZ #24986]

diff --git a/sysdeps/unix/sysv/linux/riscv/vfork.S b/sysdeps/unix/sysv/linux/riscv/vfork.S
index 67373f181b235c8717754fb0ce89b115c3bee9e6..dc173d6b47e91dc0f50933e1d2c9313d85abe083 100644 (file)
--- a/sysdeps/unix/sysv/linux/riscv/vfork.S
+++ b/sysdeps/unix/sysv/linux/riscv/vfork.S
@@ -21,9 +21,12 @@
 #include <sys/asm.h>
 #include <sysdep.h>
 #define __ASSEMBLY__
-#include <linux/sched.h>
 #include <asm/signal.h>
 
+#define CLONE_VM      0x00000100 /* Set if VM shared between processes.  */
+#define CLONE_VFORK   0x00004000 /* Set if the parent wants the child to
+                                   wake it up on mm_release.  */
+
        .text
 LEAF (__libc_vfork)