Support compilers defaulting to PIE

To support building glibc with GCC 6 configured with --enable-default-pie,
which generates PIE by default, we need to build programs as PIE.  But
elf/tst-dlopen-aout must not be built as PIE since it tests dlopen on
ET_EXEC file and PIE is ET_DYN.

	[BZ #17841]
	* Makeconfig (no-pie-ldflag): New.
	(+link): Set to $(+link-pie) if default to PIE.
	(+link-tests): Set to $(+link-pie-tests) if default to PIE.
	* config.make.in (build-pie-default): New.
	* configure.ac (libc_cv_pie_default): New.  Set to yes if -fPIE
	is default.  AC_SUBST.
	* configure: Regenerated.
	* elf/Makefile (LDFLAGS-tst-dlopen-aout): New.

ChangeLog

@@ -1,3 +1,15 @@
+2015-06-25  H.J. Lu  <hongjiu.lu@intel.com>
+
+	[BZ #17841]
+	* Makeconfig (no-pie-ldflag): New.
+	(+link): Set to $(+link-pie) if default to PIE.
+	(+link-tests): Set to $(+link-pie-tests) if default to PIE.
+	* config.make.in (build-pie-default): New.
+	* configure.ac (libc_cv_pie_default): New.  Set to yes if -fPIE
+	is default.  AC_SUBST.
+	* configure: Regenerated.
+	* elf/Makefile (LDFLAGS-tst-dlopen-aout): New.
+
 2015-06-24  Roland McGrath  <roland@hack.frob.com>
 
 	* nptl/descr.h (struct pthread): Change type of field setxid_futex

Makeconfig

@@ -442,6 +442,11 @@ endif
 # Commands for linking programs with the C library.
 ifndef +link
 ifeq (yes,$(build-shared))
+ifeq (yes,$(build-pie-default))
+no-pie-ldflag = -no-pie
++link = $(+link-pie)
++link-tests = $(+link-pie-tests)
+else
 +link-before-libc = $(CC) -nostdlib -nostartfiles -o $@ \
 	      $(sysdep-LDFLAGS) $(LDFLAGS) $(LDFLAGS-$(@F)) \
 	      $(combreloc-LDFLAGS) $(relro-LDFLAGS) $(hashstyle-LDFLAGS) \
@@ -462,6 +467,7 @@ $(+link-before-libc) $(rtld-tests-LDFLAGS) $(link-libc-tests) \
 		     $(+link-after-libc)
 $(call after-link,$@)
 endef
+endif
 else
 +link = $(+link-static)
 +link-tests = $(+link-static-tests)

NEWS

@@ -14,17 +14,17 @@ Version 2.22
   16526, 16538, 16560, 16704, 16783, 16850, 17053, 17090, 17195, 17269,
   17293, 17322, 17403, 17523, 17542, 17569, 17581, 17588, 17596, 17620,
   17621, 17628, 17631, 17692, 17711, 17715, 17776, 17779, 17792, 17836,
-  17912, 17916, 17930, 17932, 17944, 17949, 17964, 17965, 17967, 17969,
-  17977, 17978, 17987, 17991, 17996, 17998, 17999, 18007, 18019, 18020,
-  18029, 18030, 18032, 18034, 18036, 18038, 18039, 18042, 18043, 18046,
-  18047, 18049, 18068, 18080, 18093, 18100, 18104, 18110, 18111, 18116,
-  18125, 18128, 18138, 18185, 18196, 18197, 18206, 18210, 18211, 18217,
-  18219, 18220, 18221, 18234, 18244, 18245, 18247, 18287, 18319, 18324,
-  18333, 18346, 18371, 18397, 18409, 18410, 18412, 18418, 18422, 18434,
-  18444, 18468, 18469, 18470, 18479, 18483, 18495, 18496, 18497, 18498,
-  18507, 18512, 18513, 18519, 18520, 18522, 18527, 18528, 18529, 18530,
-  18532, 18533, 18534, 18536, 18539, 18540, 18542, 18544, 18545, 18546,
-  18547, 18553, 18558, 18569, 18583, 18585, 18586, 18593, 18594.
+  17841, 17912, 17916, 17930, 17932, 17944, 17949, 17964, 17965, 17967,
+  17969, 17977, 17978, 17987, 17991, 17996, 17998, 17999, 18007, 18019,
+  18020, 18029, 18030, 18032, 18034, 18036, 18038, 18039, 18042, 18043,
+  18046, 18047, 18049, 18068, 18080, 18093, 18100, 18104, 18110, 18111,
+  18116, 18125, 18128, 18138, 18185, 18196, 18197, 18206, 18210, 18211,
+  18217, 18219, 18220, 18221, 18234, 18244, 18245, 18247, 18287, 18319,
+  18324, 18333, 18346, 18371, 18397, 18409, 18410, 18412, 18418, 18422,
+  18434, 18444, 18468, 18469, 18470, 18479, 18483, 18495, 18496, 18497,
+  18498, 18507, 18512, 18513, 18519, 18520, 18522, 18527, 18528, 18529,
+  18530, 18532, 18533, 18534, 18536, 18539, 18540, 18542, 18544, 18545,
+  18546, 18547, 18553, 18558, 18569, 18583, 18585, 18586, 18593, 18594.
 
 * Cache information can be queried via sysconf() function on s390 e.g. with
   _SC_LEVEL1_ICACHE_SIZE as argument.

config.make.in

@@ -82,6 +82,7 @@ nss-crypt = @libc_cv_nss_crypt@
 # Configuration options.
 build-shared = @shared@
 build-pic-default= @libc_cv_pic_default@
+build-pie-default= @libc_cv_pie_default@
 build-profile = @profile@
 build-static-nss = @static_nss@
 add-ons = @add_ons@

configure

@@ -596,6 +596,7 @@ mach_interface_list
 DEFINES
 static_nss
 profile
+libc_cv_pie_default
 libc_cv_pic_default
 shared
 static
@@ -7317,6 +7318,26 @@ fi
 $as_echo "$libc_cv_pic_default" >&6; }
 
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -fPIE is default" >&5
+$as_echo_n "checking whether -fPIE is default... " >&6; }
+if ${libc_cv_pie_default+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  libc_cv_pie_default=yes
+cat > conftest.c <<EOF
+#if defined __PIE__ || defined __pie__ || defined PIE || defined pie
+# error PIE is default.
+#endif
+EOF
+if eval "${CC-cc} -S conftest.c 2>&5 1>&5"; then
+  libc_cv_pie_default=no
+fi
+rm -f conftest.*
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_pie_default" >&5
+$as_echo "$libc_cv_pie_default" >&6; }
+
+
 
 
 

configure.ac

@@ -2075,6 +2075,19 @@ fi
 rm -f conftest.*])
 AC_SUBST(libc_cv_pic_default)
 
+AC_CACHE_CHECK([whether -fPIE is default], libc_cv_pie_default,
+[libc_cv_pie_default=yes
+cat > conftest.c <<EOF
+#if defined __PIE__ || defined __pie__ || defined PIE || defined pie
+# error PIE is default.
+#endif
+EOF
+if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
+  libc_cv_pie_default=no
+fi
+rm -f conftest.*])
+AC_SUBST(libc_cv_pie_default)
+
 AC_SUBST(profile)
 AC_SUBST(static_nss)
 

elf/Makefile

@@ -151,6 +151,7 @@ tests += loadtest restest1 preloadtest loadfail multiload origtest resolvfail \
 #	 reldep9
 ifeq ($(build-hardcoded-path-in-tests),yes)
 tests += tst-dlopen-aout
+LDFLAGS-tst-dlopen-aout = $(no-pie-ldflag)
 endif
 test-srcs = tst-pathopt
 selinux-enabled := $(shell cat /selinux/enforce 2> /dev/null)