driver: On linux hosts disable ASLR during -freport-bug [PR119727]

Andi had a useful comment that even with the PR119727 workaround to
ignore differences in libbacktrace printed addresses, it is still better
to turn off ASLR when easily possible, e.g. in case some address leaks
in somewhere in the ICE message elsewhere, or to verify the ICE doesn't
depend on a particular library/binary load addresses.

The following patch adds a configure check and uses personality syscall
to turn off randomization for further -freport-bug subprocesses.

2025-04-14  Jakub Jelinek  <jakub@redhat.com>

	PR driver/119727
	* configure.ac (HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE): New check.
	* gcc.cc: Include sys/personality.h if
	HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE is defined.
	(try_generate_repro): Call
	personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE)
	if HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE is defined.
	* config.in: Regenerate.
	* configure: Regenerate.

4 files changed, 67 insertions, 2 deletions

diff --git a/gcc/config.in b/gcc/config.in
index 7c89cab..a79c51a 100644
--- a/gcc/config.in
+++ b/gcc/config.in
@@ -2320,6 +2320,13 @@
 #endif
 
 
+/* Define if personality and ADDR_NO_RANDOMIZE are declared in
+   sys/personality.h. */
+#ifndef USED_FOR_TARGET
+#undef HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE
+#endif
+
+
 /* Define which stat syscall is able to handle 64bit indodes. */
 #ifndef USED_FOR_TARGET
 #undef HOST_STAT_FOR_64BIT_INODES
diff --git a/gcc/configure b/gcc/configure
index ab6bec1..821f8b4 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -12694,6 +12694,42 @@ $as_echo "#define HOST_HAS_O_NONBLOCK 1" >>confdefs.h
 
 fi
 
+# Check if personality and ADDR_NO_RANDOMIZE are declared
+# in sys/personality.h
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for personality ADDR_NO_RANDOMIZE" >&5
+$as_echo_n "checking for personality ADDR_NO_RANDOMIZE... " >&6; }
+if ${ac_cv_personality_addr_no_randomize+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <sys/personality.h>
+int
+main ()
+{
+
+personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE);
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  ac_cv_personality_addr_no_randomize=yes
+else
+  ac_cv_personality_addr_no_randomize=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_personality_addr_no_randomize" >&5
+$as_echo "$ac_cv_personality_addr_no_randomize" >&6; }
+if test $ac_cv_personality_addr_no_randomize = yes; then
+
+$as_echo "#define HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE 1" >>confdefs.h
+
+fi
+
 
 # C++ Modules would like some networking features to provide the mapping
 # server.  You can still use modules without them though.
@@ -21484,7 +21520,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 21487 "configure"
+#line 21523 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -21590,7 +21626,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 21593 "configure"
+#line 21629 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/gcc/configure.ac b/gcc/configure.ac
index fca0579..3d0a4e6 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -1781,6 +1781,21 @@ if test $ac_cv_have_decl_O_NONBLOCK = yes; then
   [Define if O_NONBLOCK supported by fcntl.])
 fi
 
+# Check if personality and ADDR_NO_RANDOMIZE are declared
+# in sys/personality.h
+AC_CACHE_CHECK(for personality ADDR_NO_RANDOMIZE,
+	       ac_cv_personality_addr_no_randomize, [
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+#include <sys/personality.h>]], [[
+personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE);]])],
+[ac_cv_personality_addr_no_randomize=yes],
+[ac_cv_personality_addr_no_randomize=no])])
+if test $ac_cv_personality_addr_no_randomize = yes; then
+  AC_DEFINE(HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE, 1,
+  [Define if personality and ADDR_NO_RANDOMIZE are declared in
+sys/personality.h.])
+fi
+
 
 # C++ Modules would like some networking features to provide the mapping
 # server.  You can still use modules without them though.
diff --git a/gcc/gcc.cc b/gcc/gcc.cc
index 9064671..4fd87f2 100644
--- a/gcc/gcc.cc
+++ b/gcc/gcc.cc
@@ -30,6 +30,9 @@ compilation is specified by a string called a "spec".  */
 #define INCLUDE_STRING
 #include "config.h"
 #include "system.h"
+#ifdef HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE
+#include <sys/personality.h>
+#endif
 #include "coretypes.h"
 #include "multilib.h" /* before tm.h */
 #include "tm.h"
@@ -8003,6 +8006,10 @@ try_generate_repro (const char **argv)
   else
     new_argv[out_arg] = "-o-";
 
+#ifdef HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE
+  personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE);
+#endif
+
   int status;
   for (attempt = 0; attempt < RETRY_ICE_ATTEMPTS; ++attempt)
     {