[pypy-commit] pypy stmgc-c7: Workaround: some Linux systems start processes with a non-null %gs

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: stmgc-c7
Changeset: r72378:dd3c06b77a11
Date: 2014-07-07 12:57 +0200
http://bitbucket.org/pypy/pypy/changeset/dd3c06b77a11/

Log:	Workaround: some Linux systems start processes with a non-null %gs
	content. It seems that forcing %gs to be 0 here solves problems in
	case we have some 'late_initializations'.

diff --git a/rpython/translator/c/genc.py b/rpython/translator/c/genc.py
--- a/rpython/translator/c/genc.py
+++ b/rpython/translator/c/genc.py
@@ -795,6 +795,10 @@
     print >> f, 'char *RPython_StartupCode(void) {'
     print >> f, '\tchar *error = NULL;'
 
+    if database.with_stm:
+        print >> f, '\t/* XXX temporary workaround for late_initializations */'
+        print >> f, '\tsyscall(SYS_arch_prctl, ARCH_SET_GS, (uint64_t)0);'
+
     # put float infinities in global constants, we should not have so many of them for now to make
     # a table+loop preferable
     for dest, value in database.late_initializations:
@@ -896,6 +900,14 @@
 
     filename = targetdir.join(modulename + '.c')
     f = filename.open('w')
+    if database.with_stm:
+        print >> f, '/* XXX temporary, for SYS_arch_prctl below */'
+        print >> f, '#define _GNU_SOURCE'
+        print >> f, '#include <unistd.h>'
+        print >> f, '#include <sys/syscall.h>'
+        print >> f, '#include <sys/prctl.h>'
+        print >> f, '#include <asm/prctl.h>'
+        print >> f
     incfilename = targetdir.join('common_header.h')
     fi = incfilename.open('w')
     fi.write('#ifndef _PY_COMMON_HEADER_H\n#define _PY_COMMON_HEADER_H\n')