diff --git a/gnulib-c-stack.patch b/gnulib-c-stack.patch new file mode 100644 index 0000000..694578f --- /dev/null +++ b/gnulib-c-stack.patch @@ -0,0 +1,122 @@ +From f9e2b20a12a230efa30f1d479563ae07d276a94b Mon Sep 17 00:00:00 2001 +From: Paul Eggert +Date: Wed, 30 Sep 2020 13:50:36 -0700 +Subject: [PATCH] c-stack: stop using SIGSTKSZ +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +It’s been proposed to stop making SIGSTKSZ an integer constant: +https://sourceware.org/pipermail/libc-alpha/2020-September/118028.html +Also, using SIGSTKSZ in #if did not conform to current POSIX. +Also, avoiding SIGSTKSZ makes the code simpler and easier to grok. +* lib/c-stack.c (SIGSTKSZ): Remove. +(alternate_signal_stack): Now a 64 KiB array, for simplicity. +All uses changed. +--- + ChangeLog | 9 +++++++++ + lib/c-stack.c | 42 ++++++++++++++++++------------------------ + lib/c-stack.h | 2 +- + 3 files changed, 28 insertions(+), 25 deletions(-) + +Index: m4-1.4.18/lib/c-stack.c +=================================================================== +--- m4-1.4.18.orig/lib/c-stack.c ++++ m4-1.4.18/lib/c-stack.c +@@ -50,15 +50,6 @@ + #if ! HAVE_STACK_T && ! defined stack_t + typedef struct sigaltstack stack_t; + #endif +-#ifndef SIGSTKSZ +-# define SIGSTKSZ 16384 +-#elif HAVE_LIBSIGSEGV && SIGSTKSZ < 16384 +-/* libsigsegv 2.6 through 2.8 have a bug where some architectures use +- more than the Linux default of an 8k alternate stack when deciding +- if a fault was caused by stack overflow. */ +-# undef SIGSTKSZ +-# define SIGSTKSZ 16384 +-#endif + + #include + #include +@@ -89,6 +80,16 @@ typedef struct sigaltstack stack_t; + # endif + #endif + ++/* Storage for the alternate signal stack. ++ 64 KiB is not too large for Gnulib-using apps, and is large enough ++ for all known platforms. Smaller sizes may run into trouble. ++ For example, libsigsegv 2.6 through 2.8 have a bug where some ++ architectures use more than the Linux default of an 8 KiB alternate ++ stack when deciding if a fault was caused by stack overflow. */ ++static max_align_t alternate_signal_stack[(64 * 1024 ++ + sizeof (max_align_t) - 1) ++ / sizeof (max_align_t)]; ++ + /* The user-specified action to take when a SEGV-related program error + or stack overflow occurs. */ + static void (* volatile segv_action) (int); +@@ -128,19 +129,6 @@ die (int signo) + #if (HAVE_SIGALTSTACK && HAVE_DECL_SIGALTSTACK \ + && HAVE_STACK_OVERFLOW_HANDLING) || HAVE_LIBSIGSEGV + +-/* Storage for the alternate signal stack. */ +-static union +-{ +- char buffer[SIGSTKSZ]; +- +- /* These other members are for proper alignment. There's no +- standard way to guarantee stack alignment, but this seems enough +- in practice. */ +- long double ld; +- long l; +- void *p; +-} alternate_signal_stack; +- + static void + null_action (int signo __attribute__ ((unused))) + { +@@ -205,8 +193,8 @@ c_stack_action (void (*action) (int)) + + /* Always install the overflow handler. */ + if (stackoverflow_install_handler (overflow_handler, +- alternate_signal_stack.buffer, +- sizeof alternate_signal_stack.buffer)) ++ alternate_signal_stack, ++ sizeof alternate_signal_stack)) + { + errno = ENOTSUP; + return -1; +@@ -279,14 +267,14 @@ c_stack_action (void (*action) (int)) + stack_t st; + struct sigaction act; + st.ss_flags = 0; ++ st.ss_sp = alternate_signal_stack; ++ st.ss_size = sizeof alternate_signal_stack; + # if SIGALTSTACK_SS_REVERSED + /* Irix mistakenly treats ss_sp as the upper bound, rather than + lower bound, of the alternate stack. */ +- st.ss_sp = alternate_signal_stack.buffer + SIGSTKSZ - sizeof (void *); +- st.ss_size = sizeof alternate_signal_stack.buffer - sizeof (void *); +-# else +- st.ss_sp = alternate_signal_stack.buffer; +- st.ss_size = sizeof alternate_signal_stack.buffer; ++ st.ss_size -= sizeof (void *); ++ char *ss_sp = st.ss_sp; ++ st.ss_sp = ss_sp + st.ss_size; + # endif + r = sigaltstack (&st, NULL); + if (r != 0) +Index: m4-1.4.18/lib/c-stack.h +=================================================================== +--- m4-1.4.18.orig/lib/c-stack.h ++++ m4-1.4.18/lib/c-stack.h +@@ -34,7 +34,7 @@ + A null ACTION acts like an action that does nothing. + + ACTION must be async-signal-safe. ACTION together with its callees +- must not require more than SIGSTKSZ bytes of stack space. Also, ++ must not require more than 64 KiB of stack space. Also, + ACTION should not call longjmp, because this implementation does + not guarantee that it is safe to return to the original stack. + diff --git a/m4.changes b/m4.changes index 59f61dd..b90ef17 100644 --- a/m4.changes +++ b/m4.changes @@ -1,3 +1,8 @@ +------------------------------------------------------------------- +Mon Jul 19 12:48:42 UTC 2021 - Andreas Schwab + +- gnulib-c-stack.patch: c-stack: stop using SIGSTKSZ + ------------------------------------------------------------------- Thu Jan 23 09:25:12 UTC 2020 - Martin Pluskal diff --git a/m4.spec b/m4.spec index ef2249c..f685472 100644 --- a/m4.spec +++ b/m4.spec @@ -1,7 +1,7 @@ # # spec file for package m4 # -# Copyright (c) 2020 SUSE LLC +# Copyright (c) 2021 SUSE LLC # # All modifications and additions to the file contributed by third parties # remain the property of their copyright owners, unless otherwise agreed @@ -27,9 +27,10 @@ Source0: https://ftp.gnu.org/pub/gnu/m4/%{name}-%{version}.tar.xz Source1: https://ftp.gnu.org/pub/gnu/m4/%{name}-%{version}.tar.xz.sig Source2: https://savannah.gnu.org/project/memberlist-gpgkeys.php?group=m4&download=1#/%{name}.keyring Patch1: gnulib-libio.patch +Patch2: gnulib-c-stack.patch BuildRequires: xz Requires(post): %{install_info_prereq} -Requires(preun): %{install_info_prereq} +Requires(preun):%{install_info_prereq} Provides: base:%{_bindir}/m4 %description @@ -38,6 +39,7 @@ GNU m4 is an implementation of the traditional Unix macro processor. %prep %setup -q %patch1 -p1 +%patch2 -p1 %build %configure \