Upstream patch for non-constant SIGSTKSZ in glibc 2.34

resolves: rhbz#1975167

0001-Don-t-add-rpaths-to-libraries.patch

@@ -1,7 +1,7 @@
 From 4c7732daae8f0d2a622f91f5ff3add5c2248a2e3 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Tue, 24 Jun 2014 10:00:15 +0100
-Subject: [PATCH 1/5] Don't add rpaths to libraries.
+Subject: [PATCH 1/6] Don't add rpaths to libraries.
 
 ---
  tools/Makefile | 4 ++--
@@ -23,5 +23,5 @@ index dbad0b74f..c920a5337 100644
          > ocamlmklibconfig.ml
  
 -- 
-2.28.0.rc2
+2.32.0
 

0002-configure-Allow-user-defined-C-compiler-flags.patch

@@ -1,7 +1,7 @@
 From 441ad77a0c89f4abdf104c668d579607f338a052 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Tue, 29 May 2012 20:44:18 +0100
-Subject: [PATCH 2/5] configure: Allow user defined C compiler flags.
+Subject: [PATCH 2/6] configure: Allow user defined C compiler flags.
 
 ---
  configure.ac | 4 ++++
@@ -23,5 +23,5 @@ index aa5f26f28..5153853b7 100644
  
  # Enable SSE2 on x86 mingw to avoid using 80-bit registers.
 -- 
-2.28.0.rc2
+2.32.0
 

0003-configure-Remove-incorrect-assumption-about-cross-co.patch

@@ -1,7 +1,7 @@
 From 3318c5b805d8d6ae1d571f18f682c9f701b712e2 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Fri, 26 Apr 2019 16:16:29 +0100
-Subject: [PATCH 3/5] configure: Remove incorrect assumption about
+Subject: [PATCH 3/6] configure: Remove incorrect assumption about
  cross-compiling.
 
 See https://github.com/ocaml/ocaml/issues/8647#issuecomment-487094390
@@ -39,5 +39,5 @@ index 5153853b7..4e97474a2 100644
  # We first compute default values for as and aspp
  # If values have been given by the user then they take precedence over
 -- 
-2.28.0.rc2
+2.32.0
 

0004-Remove-configure-from-.gitattributes.patch

@@ -1,7 +1,7 @@
 From 01d8e3f82adb382fb90af15879f722e824834c84 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Sat, 18 Jan 2020 11:31:27 +0000
-Subject: [PATCH 4/5] Remove configure from .gitattributes.
+Subject: [PATCH 4/6] Remove configure from .gitattributes.
 
 It's not a binary file.
 ---
@@ -24,5 +24,5 @@ index 200eb49c6..d871764de 100644
  #   http://krlmlr.github.io/using-gitattributes-to-avoid-merge-conflicts/
  /.mailmap                merge=union
 -- 
-2.28.0.rc2
+2.32.0
 

0005-Fix-type-mismatches-between-definition-and-declarati.patch

@@ -1,7 +1,7 @@
 From 122db7141d292d63cfbe2c7d7a4280cc73194ece Mon Sep 17 00:00:00 2001
 From: Xavier Leroy <xavierleroy@users.noreply.github.com>
 Date: Wed, 5 Aug 2020 11:17:52 +0200
-Subject: [PATCH 5/5] Fix type mismatches between definition and declaration
+Subject: [PATCH 5/6] Fix type mismatches between definition and declaration
  (#9830)
 
 The C global variable caml_fl_merge and the C function
@@ -65,5 +65,5 @@ index 2b0bf1dc2..b75fb0980 100644
    return 0;
  }
 -- 
-2.28.0.rc2
+2.32.0
 

0006-Dynamically-allocate-the-alternate-signal-stack-1026.patch

@@ -0,0 +1,103 @@
+From 24a9db7784ddfcf0af2d2be2f51616ed960ae7e8 Mon Sep 17 00:00:00 2001
+From: Xavier Leroy <xavierleroy@users.noreply.github.com>
+Date: Fri, 5 Mar 2021 19:14:07 +0100
+Subject: [PATCH 6/6] Dynamically allocate the alternate signal stack (#10266)
+
+In Glibc 2.34 and later, SIGSTKSZ may not be a compile-time constant.
+It is no longer possible to statically allocate the alternate signal
+stack for the main thread, as we've been doing for the last 25 years.
+
+This commit implements dynamic allocation of the alternate signal stack
+even for the main thread.  It reuses the code already in place to allocate
+the alternate signal stack for other threads.
+
+Fixes: #10250.
+(cherry picked from commit fc9534746bf5d08a4c109f22e344cf49d5d46d54)
+---
+ runtime/caml/signals.h |  2 +-
+ runtime/signals_byt.c  |  2 +-
+ runtime/signals_nat.c  | 25 ++++++++++++++-----------
+ 3 files changed, 16 insertions(+), 13 deletions(-)
+
+diff --git a/runtime/caml/signals.h b/runtime/caml/signals.h
+index 7ec1ad3ba..98b75107b 100644
+--- a/runtime/caml/signals.h
++++ b/runtime/caml/signals.h
+@@ -82,7 +82,7 @@ void caml_set_action_pending (void);
+ value caml_do_pending_actions_exn (void);
+ value caml_process_pending_actions_with_root (value extra_root); // raises
+ int caml_set_signal_action(int signo, int action);
+-void caml_setup_stack_overflow_detection(void);
++CAMLextern int caml_setup_stack_overflow_detection(void);
+ 
+ CAMLextern void (*caml_enter_blocking_section_hook)(void);
+ CAMLextern void (*caml_leave_blocking_section_hook)(void);
+diff --git a/runtime/signals_byt.c b/runtime/signals_byt.c
+index 040de03c5..9bd2b20c6 100644
+--- a/runtime/signals_byt.c
++++ b/runtime/signals_byt.c
+@@ -86,4 +86,4 @@ int caml_set_signal_action(int signo, int action)
+     return 0;
+ }
+ 
+-void caml_setup_stack_overflow_detection(void) {}
++CAMLexport int caml_setup_stack_overflow_detection(void) { return 0; }
+diff --git a/runtime/signals_nat.c b/runtime/signals_nat.c
+index fc5a77f84..f56fce6b7 100644
+--- a/runtime/signals_nat.c
++++ b/runtime/signals_nat.c
+@@ -195,8 +195,6 @@ DECLARE_SIGNAL_HANDLER(trap_handler)
+ #error "CONTEXT_SP is required if HAS_STACK_OVERFLOW_DETECTION is defined"
+ #endif
+ 
+-static char sig_alt_stack[SIGSTKSZ];
+-
+ /* Code compiled with ocamlopt never accesses more than
+    EXTRA_STACK bytes below the stack pointer. */
+ #define EXTRA_STACK 256
+@@ -282,28 +280,33 @@ void caml_init_signals(void)
+ #endif
+ 
+ #ifdef HAS_STACK_OVERFLOW_DETECTION
+-  {
+-    stack_t stk;
++  if (caml_setup_stack_overflow_detection() != -1) {
+     struct sigaction act;
+-    stk.ss_sp = sig_alt_stack;
+-    stk.ss_size = SIGSTKSZ;
+-    stk.ss_flags = 0;
+     SET_SIGACT(act, segv_handler);
+     act.sa_flags |= SA_ONSTACK | SA_NODEFER;
+     sigemptyset(&act.sa_mask);
+-    if (sigaltstack(&stk, NULL) == 0) { sigaction(SIGSEGV, &act, NULL); }
++    sigaction(SIGSEGV, &act, NULL);
+   }
+ #endif
+ }
+ 
+-void caml_setup_stack_overflow_detection(void)
++/* Allocate and select an alternate stack for handling signals,
++   especially SIGSEGV signals.
++   Each thread needs its own alternate stack.
++   The alternate stack used to be statically-allocated for the main thread,
++   but this is incompatible with Glibc 2.34 and newer, where SIGSTKSZ
++   may not be a compile-time constant (issue #10250). */
++
++CAMLexport int caml_setup_stack_overflow_detection(void)
+ {
+ #ifdef HAS_STACK_OVERFLOW_DETECTION
+   stack_t stk;
+   stk.ss_sp = malloc(SIGSTKSZ);
++  if (stk.ss_sp == NULL) return -1;
+   stk.ss_size = SIGSTKSZ;
+   stk.ss_flags = 0;
+-  if (stk.ss_sp)
+-    sigaltstack(&stk, NULL);
++  return sigaltstack(&stk, NULL);
++#else
++  return 0;
+ #endif
+ }
+-- 
+2.32.0
+

ocaml.spec

@@ -31,7 +31,7 @@
 
 Name:           ocaml
 Version:        4.11.1
-Release:        3%{?dist}
+Release:        3%{?dist}.1
 
 Summary:        OCaml compiler and programming environment
 
@@ -65,6 +65,9 @@ Patch0004:      0004-Remove-configure-from-.gitattributes.patch
 # Fix compilation with LTO (upstream, but not in 4.11 branch).
 Patch0005:      0005-Fix-type-mismatches-between-definition-and-declarati.patch
 
+# Upstream patch for non-constant SIGSTKSZ in glibc 2.34
+Patch0006:      0006-Dynamically-allocate-the-alternate-signal-stack-1026.patch
+
 BuildRequires: make
 BuildRequires:  git
 BuildRequires:  gcc
@@ -375,6 +378,9 @@ rm -f $RPM_BUILD_ROOT%{_libdir}/ocaml/eventlog_metadata
 
 
 %changelog
+* Wed Jun 23 2021 Richard W.M. Jones <rjones@redhat.com> - 4.11.1-3.el9.1
+- Upstream patch for non-constant SIGSTKSZ in glibc 2.34
+
 * Fri Apr 16 2021 Mohan Boddu <mboddu@redhat.com> - 4.11.1-3
 - Rebuilt for RHEL 9 BETA on Apr 15th 2021. Related: rhbz#1947937