[patch] Backported patch to 2.23.

fix-bp-cannot-be-used-in-asm-here.patch (text/plain), 4.86 KB, created by Martin Kolleck on 2017-07-14 20:56:56 UTC

diff -Naur glibc-2.23/config.h.in glibc-2.23-r1/config.h.in
--- glibc-2.23/config.h.in	2017-07-14 00:29:09.830086217 +0200
+++ glibc-2.23-r1/config.h.in	2016-02-18 18:54:00.000000000 +0100
@@ -231,4 +231,8 @@
 /* PowerPC32 uses fctidz for floating point to long long conversions.  */
 #define HAVE_PPC_FCTIDZ 0
 
+/* Some compiler options may now allow to use ebp in __asm__ (used mainly
+   in i386 6 argument syscall issue).  */
+#define CAN_USE_REGISTER_ASM_EBP 0
+
 #endif
diff -Naur glibc-2.23/sysdeps/unix/sysv/linux/i386/configure glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/configure
--- glibc-2.23/sysdeps/unix/sysv/linux/i386/configure	2016-02-18 18:54:00.000000000 +0100
+++ glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/configure	2017-07-14 00:13:43.386731868 +0200
@@ -1,5 +1,44 @@
 # This file is generated from configure.ac by Autoconf.  DO NOT EDIT!
  # Local configure fragment for sysdeps/unix/sysv/linux/i386.
 
+# Check if CFLAGS allows compiler to use ebp register in inline assembly.
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if compiler flags allows ebp in inline assembly" >&5
+$as_echo_n "checking if compiler flags allows ebp in inline assembly... " >&6; }
+if ${libc_cv_can_use_register_asm_ebp+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+    void foo (int i)
+    {
+      register int reg asm ("ebp") = i;
+      asm ("# %0" : : "r" (reg));
+    }
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  libc_cv_can_use_register_asm_ebp=yes
+else
+  libc_cv_can_use_register_asm_ebp=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_can_use_register_asm_ebp" >&5
+$as_echo "$libc_cv_can_use_register_asm_ebp" >&6; }
+if test $libc_cv_can_use_register_asm_ebp = yes; then
+  $as_echo "#define CAN_USE_REGISTER_ASM_EBP 1" >>confdefs.h
+
+fi
+
 libc_cv_gcc_unwind_find_fde=yes
 ldd_rewrite_script=sysdeps/unix/sysv/linux/ldd-rewrite.sed
diff -Naur glibc-2.23/sysdeps/unix/sysv/linux/i386/configure.ac glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/configure.ac
--- glibc-2.23/sysdeps/unix/sysv/linux/i386/configure.ac	2016-02-18 18:54:00.000000000 +0100
+++ glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/configure.ac	2017-07-14 00:15:10.776733850 +0200
@@ -1,5 +1,22 @@
 GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
 # Local configure fragment for sysdeps/unix/sysv/linux/i386.
 
+# Check if CFLAGS allows compiler to use ebp register in inline assembly.
+AC_CACHE_CHECK([if compiler flags allows ebp in inline assembly],
+                libc_cv_can_use_register_asm_ebp, [
+AC_COMPILE_IFELSE(
+  [AC_LANG_PROGRAM([
+    void foo (int i)
+    {
+      register int reg asm ("ebp") = i;
+      asm ("# %0" : : "r" (reg));
+    }])],
+  [libc_cv_can_use_register_asm_ebp=yes],
+  [libc_cv_can_use_register_asm_ebp=no])
+])
+if test $libc_cv_can_use_register_asm_ebp = yes; then
+  AC_DEFINE(CAN_USE_REGISTER_ASM_EBP)
+fi
+
 libc_cv_gcc_unwind_find_fde=yes
 ldd_rewrite_script=sysdeps/unix/sysv/linux/ldd-rewrite.sed
diff -Naur glibc-2.23/sysdeps/unix/sysv/linux/i386/Makefile glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/Makefile
--- glibc-2.23/sysdeps/unix/sysv/linux/i386/Makefile	2016-02-18 18:54:00.000000000 +0100
+++ glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/Makefile	2017-07-14 00:12:08.030063038 +0200
@@ -3,19 +3,6 @@
 
 ifeq ($(subdir),misc)
 sysdep_routines += ioperm iopl vm86
-# %ebp may be used to pass the 6th argument to syscall.
-CFLAGS-epoll_pwait.o += -fomit-frame-pointer
-CFLAGS-epoll_pwait.os += -fomit-frame-pointer
-CFLAGS-mmap.o += -fomit-frame-pointer
-CFLAGS-mmap.os += -fomit-frame-pointer
-CFLAGS-mmap64.o += -fomit-frame-pointer
-CFLAGS-mmap64.os += -fomit-frame-pointer
-endif
-
-ifeq ($(subdir),sysvipc)
-# %ebp may be used to pass the 6th argument to syscall.
-CFLAGS-semtimedop.o += -fomit-frame-pointer
-CFLAGS-semtimedop.os += -fomit-frame-pointer
 endif
 
 ifeq ($(subdir),elf)
diff -Naur glibc-2.23/sysdeps/unix/sysv/linux/i386/sysdep.h glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/sysdep.h
--- glibc-2.23/sysdeps/unix/sysv/linux/i386/sysdep.h	2016-02-18 18:54:00.000000000 +0100
+++ glibc-2.23-r1/sysdeps/unix/sysv/linux/i386/sysdep.h	2017-07-14 00:16:09.406735180 +0200
@@ -44,9 +44,9 @@
 /* Since GCC 5 and above can properly spill %ebx with PIC when needed,
    we can inline syscalls with 6 arguments if GCC 5 or above is used
    to compile glibc.  Disable GCC 5 optimization when compiling for
-   profiling since asm ("ebp") can't be used to put the 6th argument
-   in %ebp for syscall.  */
-#if __GNUC_PREREQ (5,0) && !defined PROF
+   profiling or when -fno-omit-frame-pointer is used since asm ("ebp")
+   can't be used to put the 6th argument in %ebp for syscall.  */
+#if __GNUC_PREREQ (5,0) && !defined PROF && CAN_USE_REGISTER_ASM_EBP
 # define OPTIMIZE_FOR_GCC_5
 #endif