main/libc0.9.32: improve the stack unwinding fix

should now work with all syscalls

2 files changed, 92 insertions, 32 deletions

diff --git a/main/libc0.9.32/0001-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch b/main/libc0.9.32/0001-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
index 87a1758523..62c1456949 100644
--- a/main/libc0.9.32/0001-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
+++ b/main/libc0.9.32/0001-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
@@ -1,7 +1,7 @@
-From 80db5b343bd44806881d400a8627cb526ffccee7 Mon Sep 17 00:00:00 2001
+From 5f72f80e7ea0e3429c28ff5de7ca88cdd95e8904 Mon Sep 17 00:00:00 2001
 From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
 Date: Thu, 10 Nov 2011 09:36:44 +0200
-Subject: [PATCH] libc/x86: fix stack unwinding and backtrace information
+Subject: [PATCHv2] libc/x86: fix stack unwinding and backtrace information
 MIME-Version: 1.0
 Content-Type: text/plain; charset=UTF-8
 Content-Transfer-Encoding: 8bit
@@ -11,6 +11,7 @@ for proper stack unwinding.
 
 This patch adds the CFI information to:
  * syscalls (so we get proper backtrace even for release builds)
+   the ebx hack was removed as it would complicate the CFI generation
  * new thread stub function (so the backtrace is clean for user
    created threads)
 
@@ -25,13 +26,13 @@ signal return frame.
 
 Signed-off-by: Timo Teräs <timo.teras@iki.fi>
 ---
- libc/sysdeps/linux/i386/bits/syscalls.h |   13 +++++++++----
- libc/sysdeps/linux/i386/clone.S         |   17 +++++++++++++++++
- libc/sysdeps/linux/i386/sigaction.c     |    4 ++++
- 3 files changed, 30 insertions(+), 4 deletions(-)
+ libc/sysdeps/linux/i386/bits/syscalls.h |   82 +++----------------------------
+ libc/sysdeps/linux/i386/clone.S         |   17 ++++++
+ libc/sysdeps/linux/i386/sigaction.c     |    4 ++
+ 3 files changed, 28 insertions(+), 75 deletions(-)
 
 diff --git a/libc/sysdeps/linux/i386/bits/syscalls.h b/libc/sysdeps/linux/i386/bits/syscalls.h
-index eeafb3a..47d0b4c 100644
+index eeafb3a..1f60a44 100644
 --- a/libc/sysdeps/linux/i386/bits/syscalls.h
 +++ b/libc/sysdeps/linux/i386/bits/syscalls.h
 @@ -13,6 +13,7 @@
@@ -42,25 +43,83 @@ index eeafb3a..47d0b4c 100644
  
  #define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
  ({ \
-@@ -71,6 +72,8 @@ __asm__ (
-        ".if 1 - \\name\n\t"    /* if reg!=ebx... */
-        ".if 2 - \\name\n\t"    /* if reg can't be clobbered... */
-        "pushl %ebx\n\t"        /* save ebx on stack */
-+       CFI_ADJUST_CFA_OFFSET(4) "\n\t"
-+       CFI_REL_OFFSET(ebx, 0) "\n\t"
-        ".else\n\t"
-        "xchgl \\reg, %ebx\n\t" /* else save ebx in reg, and load reg to ebx */
-        ".endif\n\t"
-@@ -89,6 +92,8 @@ __asm__ (
-        ".if 1 - \\name\n\t"
-        ".if 2 - \\name\n\t"    /* if reg can't be clobbered... */
-        "popl %ebx\n\t"         /* restore ebx from stack */
-+       CFI_ADJUST_CFA_OFFSET(-4) "\n\t"
-+       CFI_RESTORE(ebx) "\n\t"
-        ".else\n\t"
-        "xchgl \\reg, %ebx\n\t" /* else restore ebx from reg */
-        ".endif\n\t"
-@@ -106,7 +111,7 @@ __asm__ (
+@@ -31,90 +32,21 @@
+ 
+ #if 1 /* defined __PIC__ || defined __pic__ */
+ 
+-/* This code avoids pushing/popping ebx as much as possible.
+- * I think the main reason was that older GCCs had problems
+- * with proper saving/restoring of ebx if "b" constraint was used,
+- * which was breaking -fPIC code really badly.
+- * At least gcc 4.2.x seems to not need these tricks anymore,
+- * but this code is still useful because it often avoids
+- * using stack for saving ebx.
+- * Keeping it unconditionally enabled for now.
+- */
+-
+-/* We need some help from the assembler to generate optimal code.
+- * We define some macros here which later will be used.  */
+-/* gcc>=4.6 with LTO need the same guards as IMA (a.k.a --combine) did.
+- * See gcc.gnu.org/PR47577  */
+-/* FIXME: drop these b* macros! */
+-
+-__asm__ (
+-#if defined __DOMULTI__ || __GNUC_PREREQ (4, 6)
+-       /* Protect against asm macro redefinition (happens in __DOMULTI__ mode).
+-        * Unfortunately, it ends up visible in .o files. */
+-       ".ifndef _BITS_SYSCALLS_ASM\n\t"
+-       ".set _BITS_SYSCALLS_ASM,1\n\t"
+-#endif
+-       ".L__X'%ebx = 1\n\t"
+-       ".L__X'%ecx = 2\n\t"
+-       ".L__X'%edx = 2\n\t"
+-       ".L__X'%eax = 3\n\t"
+-       ".L__X'%esi = 3\n\t"
+-       ".L__X'%edi = 3\n\t"
+-       ".L__X'%ebp = 3\n\t"
+-       ".L__X'%esp = 3\n\t"
+-
+-       /* Loading param #1 (ebx) is done by loading it into
+-        * another register, and then performing bpushl+bmovl,
+-        * since we must preserve ebx */
+-
+-       ".macro bpushl name reg\n\t"
+-       ".if 1 - \\name\n\t"    /* if reg!=ebx... */
+-       ".if 2 - \\name\n\t"    /* if reg can't be clobbered... */
+-       "pushl %ebx\n\t"        /* save ebx on stack */
+-       ".else\n\t"
+-       "xchgl \\reg, %ebx\n\t" /* else save ebx in reg, and load reg to ebx */
+-       ".endif\n\t"
+-       ".endif\n\t"
+-       ".endm\n\t"
+-
+-       ".macro bmovl name reg\n\t"
+-       ".if 1 - \\name\n\t"
+-       ".if 2 - \\name\n\t"    /* if reg can't be clobbered... */
+-       "movl \\reg, %ebx\n\t"  /* load reg to ebx */
+-       ".endif\n\t"
+-       ".endif\n\t"
+-       ".endm\n\t"
+-
+-       ".macro bpopl name reg\n\t"
+-       ".if 1 - \\name\n\t"
+-       ".if 2 - \\name\n\t"    /* if reg can't be clobbered... */
+-       "popl %ebx\n\t"         /* restore ebx from stack */
+-       ".else\n\t"
+-       "xchgl \\reg, %ebx\n\t" /* else restore ebx from reg */
+-       ".endif\n\t"
+-       ".endif\n\t"
+-       ".endm\n\t"
+-
+-#if defined __DOMULTI__ || __GNUC_PREREQ (4, 6)
+-       ".endif\n\t" /* _BITS_SYSCALLS_ASM */
+-#endif
+-);
+-
+ #define LOADARGS_0
+-#define LOADARGS_1  "bpushl .L__X'%k2, %k2\n\t" "bmovl .L__X'%k2, %k2\n\t"
++#define LOADARGS_1  "push %%ebx\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebx, 0) "\n\t" "movl %k2, %%ebx\n\t"
+ #define LOADARGS_2  LOADARGS_1
  #define LOADARGS_3  LOADARGS_1
  #define LOADARGS_4  LOADARGS_1
  #define LOADARGS_5  LOADARGS_1
@@ -68,8 +127,9 @@ index eeafb3a..47d0b4c 100644
 +#define LOADARGS_6  LOADARGS_1 "push %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebp, 0) "\n\t" "movl %7, %%ebp\n\t"
  
  #define RESTOREARGS_0
- #define RESTOREARGS_1  "bpopl .L__X'%k2, %k2\n\t"
-@@ -114,7 +119,7 @@ __asm__ (
+-#define RESTOREARGS_1  "bpopl .L__X'%k2, %k2\n\t"
++#define RESTOREARGS_1  "pop %%ebx\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebx) "\n\t" RESTOREARGS_0
+ #define RESTOREARGS_2  RESTOREARGS_1
  #define RESTOREARGS_3  RESTOREARGS_1
  #define RESTOREARGS_4  RESTOREARGS_1
  #define RESTOREARGS_5  RESTOREARGS_1
@@ -78,7 +138,7 @@ index eeafb3a..47d0b4c 100644
  
  #define ASMFMT_0()
  /* "acdSD" constraint would work too, but "SD" would use esi/edi and cause
-@@ -162,7 +167,7 @@ __asm__ (
+@@ -162,7 +94,7 @@ __asm__ (
  #define LOADARGS_3
  #define LOADARGS_4
  #define LOADARGS_5
@@ -87,7 +147,7 @@ index eeafb3a..47d0b4c 100644
  
  #define RESTOREARGS_0
  #define RESTOREARGS_1
-@@ -170,7 +175,7 @@ __asm__ (
+@@ -170,7 +102,7 @@ __asm__ (
  #define RESTOREARGS_3
  #define RESTOREARGS_4
  #define RESTOREARGS_5
diff --git a/main/libc0.9.32/APKBUILD b/main/libc0.9.32/APKBUILD
index 54d69866cc..8fc93dadaa 100644
--- a/main/libc0.9.32/APKBUILD
+++ b/main/libc0.9.32/APKBUILD
@@ -4,7 +4,7 @@ pkgname=libc$_abiver
 _gitver=
 pkgver=0.9.32
 _ver=${pkgver/_/-}
-pkgrel=7
+pkgrel=8
 pkgdesc="C library for developing embedded Linux systems"
 url=http://uclibc.org
 license="LGPL-2"
@@ -145,7 +145,7 @@ b4fb68ad3d0e8331b1b40c30eb21dfdc  0002-stdlib-fix-arc4random-return-type-to-u_in
 30f27fe51fdc4d121166ad2af18dfb8d  0001-malloc-standard-synchronize-on-fork.patch
 2548d9f470c9a5b2c117ec3d6f35c105  0001-time-fix-parsing-of-tzdata-files-where-off_t-is-64-b.patch
 9e1ffc8dae55f4489c770f284734804f  0001-getaddrinfo-allow-numeric-service-without-any-hints.patch
-1aed313e59ca9bc15f87273d4b3d4fde  0001-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
+e814d39ab0adab58d69396ac0b9acdea  0001-libc-x86-fix-stack-unwinding-and-backtrace-informati.patch
 40e9c7f017cc81ee5b19ead000b9b6b7  libm-cabsf.patch
 42416385763f7cd50775ed9bfaf2d59e  libm-cexp.patch
 7c47e9cb284b0da8df6ed2096b2c9c66  uclibc-ubacktrace-asneeded-fix.patch