From d89f5b20b2e00241eebd8ca592520c429d6f0d4c Mon Sep 17 00:00:00 2001 From: Jeffrey Yasskin Date: Fri, 9 Jan 2009 16:47:07 +0000 Subject: [PATCH] Fix issue 4884, preventing a crash in the socket code when python is compiled with llvm-gcc and run with a glibc <2.10. --- Include/pyport.h | 9 +++++++++ Modules/socketmodule.c | 6 +++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/Include/pyport.h b/Include/pyport.h index 15c8644f56..54411f2597 100644 --- a/Include/pyport.h +++ b/Include/pyport.h @@ -709,6 +709,15 @@ typedef struct fd_set { #define Py_FORMAT_PARSETUPLE(func,p1,p2) #endif +/* + * Specify alignment on compilers that support it. + */ +#if defined(__GNUC__) && __GNUC__ >= 3 +#define Py_ALIGNED(x) __attribute__((aligned(x))) +#else +#define Py_ALIGNED(x) +#endif + /* Eliminate end-of-loop code not reached warnings from SunPro C * when using do{...}while(0) macros */ diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c index deff28a1be..c1e3cfe175 100644 --- a/Modules/socketmodule.c +++ b/Modules/socketmodule.c @@ -3334,7 +3334,11 @@ socket_gethostbyaddr(PyObject *self, PyObject *args) #ifdef HAVE_GETHOSTBYNAME_R_3_ARG struct hostent_data data; #else - char buf[16384]; + /* glibcs up to 2.10 assume that the buf argument to + gethostbyaddr_r is 8-byte aligned, which at least llvm-gcc + does not ensure. The attribute below instructs the compiler + to maintain this alignment. */ + char buf[16384] Py_ALIGNED(8); int buf_len = (sizeof buf) - 1; int errnop; #endif -- 2.50.1