[PATCH regression] os: call va_start() before va_copy()

[Peter Hutterer]

Otherwise we copy random stuff, which is less than ideal.
Introduced in a818b305989bbcde4e585112a7ee70cbc0b14a92

Test-case: start server as user other than root, segfault triggered when
xf86OpenConsole's calls FatalError.

Backtrace:
0: ./hw/xfree86/Xorg (xorg_backtrace+0x41) [0x47a9d9]
1: ./hw/xfree86/Xorg (0x400000+0x81cfc) [0x481cfc]
2: /lib64/libpthread.so.0 (0x3d1e200000+0xf500) [0x3d1e20f500]
3: /lib64/libc.so.6 (_IO_vfprintf+0x4758) [0x3d1de4bb98]
4: /lib64/libc.so.6 (vsnprintf+0xa2) [0x3d1de76b82]
5: ./hw/xfree86/Xorg (LogVWrite+0x10c) [0x4808d1]
6: ./hw/xfree86/Xorg (VErrorF+0x25) [0x4815f2]
7: ./hw/xfree86/Xorg (FatalError+0xc4) [0x48157b]
8: ./hw/xfree86/Xorg (LockServer+0x3f8) [0x482c25]
9: ./hw/xfree86/Xorg (OsInit+0x3f7) [0x4821a2]
10: ./hw/xfree86/Xorg (0x400000+0x8fbd5) [0x48fbd5]
11: /lib64/libc.so.6 (__libc_start_main+0xed) [0x3d1de2169d]
12: ./hw/xfree86/Xorg (0x400000+0x212f9) [0x4212f9]

Segmentation fault at address (nil)

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
 os/log.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/os/log.c b/os/log.c
index 9a71969..e554a8c 100644
--- a/os/log.c
+++ b/os/log.c
@@ -601,6 +601,7 @@ FatalError(const char *f, ...)
     else
         ErrorF("\nFatal server error:\n");
 
+    va_start(args, f);
     /* Make a copy for OsVendorFatalError */
     va_copy(args2, args);
 
-- 
1.7.7.6