On 07/11/2012 00:14, Magnus Granberg wrote: > 2012-11-07 Magnus Granberg <zorry@gentoo... > Pavel Labushev <pavel.labushev@runbox... > > * configure.ac: Add --enable-pax_emutramp for PaX enable kernels. > * src/closures.c: Add emutramp_enabled_check. Don't mmap with PROT_EXEC > on PaX enable Kernels. > * README: Add description for --enable-pax_emutramp. > * fficonfig.h.in: Rebuilt. > * configure.ac: Rebuilt.
Hi lists, There was a small problem with this (upstream relative to gcc) libffi patch(*). The entire #ifdef FFI_MMAP_EXEC_EMUTRAMP_PAX clause is contained within an outer #if !defined(X86_WIN32) && !defined(X86_WIN64) clause. That means that Windows platforms don't get the default definition of is_emutramp_enabled() supplied by the #else clause. However, is_emutramp_enabled() is unconditionally referenced in dlmmap(), and without this default definition Windows targets fail to compile. The attached patch fixes this by moving the #else clause with the default is_emutramp_enabled() definition to a standalone #ifndef clause outside any enclosing conditional compilation test. I couldn't think of a better way to do it; the #if !(windows) clause is followed by a #elif (cygwin/interix) clause, so I'd have had to put a default definition in there and also a second one in a subsequent unconditional #else if I didn't move it out of the enclosing #if scope altogether. Gcc-patches: Assuming AG approves, can we commit this without waiting for an upstream libffi release and doing a full merge? Currently GCC HEAD won't build libffi (and hence libjava) without it. 2013-02-21 Dave Korn <dave.korn.cyg...@gmail.com> * src/closures.c (is_emutramp_enabled [!FFI_MMAP_EXEC_EMUTRAMP_PAX]): Move default definition outside enclosing #if scope. cheers, DaveK -- (*) - Patch: http://sourceware.org/ml/libffi-discuss/2012/msg00269.html - Thread: http://sourceware.org/ml/libffi-discuss/2012/threads.html#00247
Index: src/closures.c =================================================================== --- src/closures.c (revision 196167) +++ src/closures.c (working copy) @@ -189,8 +189,6 @@ emutramp_enabled_check (void) #define is_emutramp_enabled() (emutramp_enabled >= 0 ? emutramp_enabled \ : (emutramp_enabled = emutramp_enabled_check ())) -#else -#define is_emutramp_enabled() 0 #endif /* FFI_MMAP_EXEC_EMUTRAMP_PAX */ #elif defined (__CYGWIN__) || defined(__INTERIX) @@ -202,6 +200,10 @@ emutramp_enabled_check (void) #endif /* !defined(X86_WIN32) && !defined(X86_WIN64) */ +#ifndef FFI_MMAP_EXEC_EMUTRAMP_PAX +#define is_emutramp_enabled() 0 +#endif /* FFI_MMAP_EXEC_EMUTRAMP_PAX */ + /* Declare all functions defined in dlmalloc.c as static. */ static void *dlmalloc(size_t); static void dlfree(void*);