From: Ulf Hermann <ulf.hermann@qt.io>
To: <elfutils-devel@sourceware.org>
Subject: [PATCH] Check for -z,defs, -z,relro, -fPIC, -fPIE before using them
Date: Thu, 27 Apr 2017 17:51:00 -0000 [thread overview]
Message-ID: <968ddb1f-fdc5-dd72-b127-a087a4e2600c@qt.io> (raw)
On windows those aren't needed because the link results are no ELF
files and all code is position independent anyway. gcc then complains
about them, which is in turn caught by -Werror.
Signed-off-by: Ulf Hermann <ulf.hermann@qt.io>
---
ChangeLog | 5 +++++
backends/ChangeLog | 4 ++++
backends/Makefile.am | 4 ++--
config/ChangeLog | 4 ++++
config/eu.am | 4 ++--
configure.ac | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++--
lib/ChangeLog | 4 ++++
lib/Makefile.am | 2 +-
libasm/ChangeLog | 4 ++++
libasm/Makefile.am | 2 +-
libcpu/ChangeLog | 4 ++++
libcpu/Makefile.am | 2 +-
libdw/ChangeLog | 4 ++++
libdw/Makefile.am | 4 ++--
libebl/ChangeLog | 4 ++++
libebl/Makefile.am | 2 +-
libelf/ChangeLog | 4 ++++
libelf/Makefile.am | 6 +++---
libgnu/Makefile.am | 2 +-
tests/ChangeLog | 4 ++++
tests/Makefile.am | 4 ++--
21 files changed, 111 insertions(+), 18 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 6fe525c..36c3cc7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+ * configure.ac: Check if -fPIC, -fPIE, -Wl,-z,defs,
+ and -Wl,-z,relro are supported by the compiler.
+
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
* configure.ac: Drop checks for memrchr, rawmemchr, mempcpy, argp.
2017-04-21 Ulf Hermann <ulf.hermann@qt.io>
diff --git a/backends/ChangeLog b/backends/ChangeLog
index 594aa98..baeb7b9 100644
--- a/backends/ChangeLog
+++ b/backends/ChangeLog
@@ -1,3 +1,7 @@
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
+ * Makefile.am: Use dso_LDFLAGS.
+
2017-04-21 Ulf Hermann <ulf.hermann@qt.io>
* Makefile.am: Link backends against libgnu.a if requested.
diff --git a/backends/Makefile.am b/backends/Makefile.am
index 5dcb3e1..3e1992e 100644
--- a/backends/Makefile.am
+++ b/backends/Makefile.am
@@ -138,10 +138,10 @@ libebl_%.so libebl_%.map: libebl_%_pic.a $(libelf) $(libdw) $(libgnu)
@rm -f $(@:.so=.map)
$(AM_V_at)echo 'ELFUTILS_$(PACKAGE_VERSION) { global: $*_init; local: *; };' \
> $(@:.so=.map)
- $(AM_V_CCLD)$(LINK) -shared -o $(@:.map=.so) \
+ $(AM_V_CCLD)$(LINK) $(dso_LDFLAGS) -o $(@:.map=.so) \
-Wl,--whole-archive $< $(cpu_$*) -Wl,--no-whole-archive \
-Wl,--version-script,$(@:.so=.map) \
- -Wl,-z,defs -Wl,--as-needed $(libelf) $(libdw) $(libgnu)
+ -Wl,--as-needed $(libelf) $(libdw) $(libgnu)
@$(textrel_check)
libebl_i386.so: $(cpu_i386)
diff --git a/config/ChangeLog b/config/ChangeLog
index 756bab6..59569e3 100644
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,3 +1,7 @@
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
+ * eu.am: Use fpic_CFLAGS.
+
2017-04-21 Ulf Hermann <ulf.hermann@qt.io>
* eu.am: Add $(top_srcdir)libgnu and $(top_builddir)/libgnu to -I if requested.
diff --git a/config/eu.am b/config/eu.am
index 11c2fec..bc8c767 100644
--- a/config/eu.am
+++ b/config/eu.am
@@ -89,14 +89,14 @@ endif
%.os: %.c %.o
if AMDEP
- $(AM_V_CC)if $(COMPILE.os) -c -o $@ -fPIC $(DEFS.os) -MT $@ -MD -MP \
+ $(AM_V_CC)if $(COMPILE.os) -c -o $@ $(fpic_CFLAGS) $(DEFS.os) -MT $@ -MD -MP \
-MF "$(DEPDIR)/$*.Tpo" `test -f '$<' || echo '$(srcdir)/'`$<; \
then cat "$(DEPDIR)/$*.Tpo" >> "$(DEPDIR)/$*.Po"; \
rm -f "$(DEPDIR)/$*.Tpo"; \
else rm -f "$(DEPDIR)/$*.Tpo"; exit 1; \
fi
else
- $(AM_V_CC)$(COMPILE.os) -c -o $@ -fPIC $(DEFS.os) $<
+ $(AM_V_CC)$(COMPILE.os) -c -o $@ $(fpic_CFLAGS) $(DEFS.os) $<
endif
CLEANFILES = *.gcno *.gcda
diff --git a/configure.ac b/configure.ac
index a48b13e..107762f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -136,13 +136,65 @@ CFLAGS="$old_CFLAGS"])
AS_IF([test "x$ac_cv_c99" != xyes],
AC_MSG_ERROR([gcc with GNU99 support required]))
+AC_CACHE_CHECK([whether gcc supports -fPIC], ac_cv_fpic, [dnl
+save_CFLAGS="$CFLAGS"
+CFLAGS="$save_CFLAGS -fPIC -Werror"
+AC_COMPILE_IFELSE([AC_LANG_SOURCE()], ac_cv_fpic=yes, ac_cv_fpic=no)
+CFLAGS="$save_CFLAGS"
+])
+if test "$ac_cv_fpic" = "yes"; then
+ fpic_CFLAGS="-fPIC"
+else
+ fpic_CFLAGS=""
+fi
+AC_SUBST([fpic_CFLAGS])
+
+AC_CACHE_CHECK([whether gcc supports -fPIE], ac_cv_fpie, [dnl
+save_CFLAGS="$CFLAGS"
+CFLAGS="$save_CFLAGS -fPIE -Werror"
+AC_COMPILE_IFELSE([AC_LANG_SOURCE()], ac_cv_fpie=yes, ac_cv_fpie=no)
+CFLAGS="$save_CFLAGS"
+])
+if test "$ac_cv_fpie" = "yes"; then
+ fpie_CFLAGS="-fPIE"
+else
+ fpie_CFLAGS=""
+fi
+AC_SUBST([fpie_CFLAGS])
+
+dso_LDFLAGS="-shared"
+
+ZDEFS_LDFLAGS="-Wl,-z,defs"
+AC_CACHE_CHECK([whether gcc supports $ZDEFS_LDFLAGS], ac_cv_zdefs, [dnl
+save_LDFLAGS="$LDFLAGS"
+LDFLAGS="$ZDEFS_LDFLAGS $save_LDFLAGS"
+AC_LINK_IFELSE([AC_LANG_PROGRAM()], ac_cv_zdefs=yes, ac_cv_zdefs=no)
+LDFLAGS="$save_LDFLAGS"
+])
+if test "$ac_cv_zdefs" = "yes"; then
+ dso_LDFLAGS="$dso_LDFLAGS $ZDEFS_LDFLAGS"
+fi
+
+ZRELRO_LDFLAGS="-Wl,-z,relro"
+AC_CACHE_CHECK([whether gcc supports $ZRELRO_LDFLAGS], ac_cv_zrelro, [dnl
+save_LDFLAGS="$LDFLAGS"
+LDFLAGS="$ZRELRO_LDFLAGS $save_LDFLAGS"
+AC_LINK_IFELSE([AC_LANG_PROGRAM()], ac_cv_zrelro=yes, ac_cv_zrelro=no)
+LDFLAGS="$save_LDFLAGS"
+])
+if test "$ac_cv_zrelro" = "yes"; then
+ dso_LDFLAGS="$dso_LDFLAGS $ZRELRO_LDFLAGS"
+fi
+
+AC_SUBST([dso_LDFLAGS])
+
AC_CACHE_CHECK([for __thread support], ac_cv_tls, [dnl
# Use the same flags that we use for our DSOs, so the test is representative.
# Some old compiler/linker/libc combinations fail some ways and not others.
save_CFLAGS="$CFLAGS"
save_LDFLAGS="$LDFLAGS"
-CFLAGS="-fPIC $CFLAGS"
-LDFLAGS="-shared -Wl,-z,defs,-z,relro $LDFLAGS"
+CFLAGS="$fpic_CFLAGS $CFLAGS"
+LDFLAGS="$dso_LDFLAGS $LDFLAGS"
AC_LINK_IFELSE([dnl
AC_LANG_PROGRAM([[#include <stdlib.h>
#undef __thread
diff --git a/lib/ChangeLog b/lib/ChangeLog
index 82c009e..605b9b9 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,5 +1,9 @@
2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+ * Makefile.am: Use fpic_CFLAGS.
+
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
* system.h: Drop mempcpy replacement.
* xstrndup.c: Don't include system.h.
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 7a65eb9..17d16d0 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -28,7 +28,7 @@
## not, see <http://www.gnu.org/licenses/>.
##
include $(top_srcdir)/config/eu.am
-AM_CFLAGS += -fPIC
+AM_CFLAGS += $(fpic_CFLAGS)
AM_CPPFLAGS += -I$(srcdir)/../libelf
noinst_LIBRARIES = libeu.a
diff --git a/libasm/ChangeLog b/libasm/ChangeLog
index 80aa7de..971492a 100644
--- a/libasm/ChangeLog
+++ b/libasm/ChangeLog
@@ -1,5 +1,9 @@
2017-02-27 Ulf Hermann <ulf.hermann@qt.io>
+ * Makefile.am: Use dso_LDFLAGS.
+
+2017-02-27 Ulf Hermann <ulf.hermann@qt.io>
+
* disasm_str.c: Don't include system.h
2017-02-21 Ulf Hermann <ulf.hermann@qt.io>
diff --git a/libasm/Makefile.am b/libasm/Makefile.am
index 8713070..a5fc9fc 100644
--- a/libasm/Makefile.am
+++ b/libasm/Makefile.am
@@ -65,7 +65,7 @@ endif
libasm_so_SOURCES =
libasm.so$(EXEEXT): libasm_pic.a libasm.map
- $(AM_V_CCLD)$(LINK) -shared -o $@ -Wl,--whole-archive,$<,--no-whole-archive \
+ $(AM_V_CCLD)$(LINK) $(dso_LDFLAGS) -o $@ -Wl,--whole-archive,$<,--no-whole-archive \
-Wl,--version-script,$(srcdir)/libasm.map,--no-undefined \
-Wl,--soname,$@.$(VERSION) \
../libebl/libebl.a ../libelf/libelf.so ../libdw/libdw.so \
diff --git a/libcpu/ChangeLog b/libcpu/ChangeLog
index 9235b1b..ef5da58 100644
--- a/libcpu/ChangeLog
+++ b/libcpu/ChangeLog
@@ -1,3 +1,7 @@
+2017-02-27 Ulf Hermann <ulf.hermann@qt.io>
+
+ * Makefile.am: Use fpic_CFLAGS.
+
2017-02-21 Ulf Hermann <ulf.hermann@qt.io>
* Makefile.am: Link gendis agaist libgnu.a if requested.
diff --git a/libcpu/Makefile.am b/libcpu/Makefile.am
index 30a6799..9ca0f43 100644
--- a/libcpu/Makefile.am
+++ b/libcpu/Makefile.am
@@ -30,7 +30,7 @@
include $(top_srcdir)/config/eu.am
AM_CPPFLAGS += -I$(srcdir)/../libelf -I$(srcdir)/../libebl \
-I$(srcdir)/../libdw -I$(srcdir)/../libasm
-AM_CFLAGS += -fPIC -fdollars-in-identifiers
+AM_CFLAGS += $(fpic_CFLAGS) -fdollars-in-identifiers
LEXCOMPILE = $(LEX) $(LFLAGS) $(AM_LFLAGS) -P$(<F:lex.l=)
LEX_OUTPUT_ROOT = lex.$(<F:lex.l=)
AM_YFLAGS = -p$(<F:parse.y=)
diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index 6e11181..d15c861 100644
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,5 +1,9 @@
2017-02-27 Ulf Hermann <ulf.hermann@qt.io>
+ * Makefile.am: Use fpic_CFLAGS and dso_LDFLAGS.
+
+2017-02-27 Ulf Hermann <ulf.hermann@qt.io>
+
* Makefile.am: Remove argp_LDADD.
2017-02-21 Ulf Hermann <ulf.hermann@qt.io>
diff --git a/libdw/Makefile.am b/libdw/Makefile.am
index 8843062..7b69f6a 100644
--- a/libdw/Makefile.am
+++ b/libdw/Makefile.am
@@ -29,7 +29,7 @@
##
include $(top_srcdir)/config/eu.am
if BUILD_STATIC
-AM_CFLAGS += -fPIC
+AM_CFLAGS += $(fpic_CFLAGS)
endif
AM_CPPFLAGS += -I$(srcdir)/../libelf
VERSION = 1
@@ -114,7 +114,7 @@ libdw.so$(EXEEXT): $(srcdir)/libdw.map libdw_pic.a ../libdwelf/libdwelf_pic.a \
../libelf/libelf.so
# The rpath is necessary for libebl because its $ORIGIN use will
# not fly in a setuid executable that links in libdw.
- $(AM_V_CCLD)$(LINK) -shared -o $@ -Wl,--soname,$@.$(VERSION),-z,defs \
+ $(AM_V_CCLD)$(LINK) $(dso_LDFLAGS) -o $@ -Wl,--soname,$@.$(VERSION) \
-Wl,--enable-new-dtags,-rpath,$(pkglibdir) \
-Wl,--version-script,$<,--no-undefined \
-Wl,--whole-archive $(filter-out $<,$^) -Wl,--no-whole-archive\
diff --git a/libebl/ChangeLog b/libebl/ChangeLog
index 0605083..56b0421 100644
--- a/libebl/ChangeLog
+++ b/libebl/ChangeLog
@@ -1,5 +1,9 @@
2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+ * Makefile.am: Use fpic_CFLAGS.
+
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
* eblmachineflagname.c: Don't include system.h.
* eblopenbackend.c: Likewise.
diff --git a/libebl/Makefile.am b/libebl/Makefile.am
index 6f945eb..60d0e73 100644
--- a/libebl/Makefile.am
+++ b/libebl/Makefile.am
@@ -28,7 +28,7 @@
## not, see <http://www.gnu.org/licenses/>.
##
include $(top_srcdir)/config/eu.am
-AM_CFLAGS += -fPIC
+AM_CFLAGS += $(fpic_CFLAGS)
AM_CPPFLAGS += -I$(srcdir)/../libelf -I$(srcdir)/../libdw -I$(srcdir)/../libasm
VERSION = 1
LIBEBL_SUBDIR = @LIBEBL_SUBDIR@
diff --git a/libelf/ChangeLog b/libelf/ChangeLog
index 9165634..1c6cce2 100644
--- a/libelf/ChangeLog
+++ b/libelf/ChangeLog
@@ -1,5 +1,9 @@
2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+ * Makefile.am: Use fpic_CFLAGS and dso_LDFLAGS.
+
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
* elf_getarsym.c: Don't replace rawmemchr.
* elf_strptr.c: Don't replace memrchr.
diff --git a/libelf/Makefile.am b/libelf/Makefile.am
index d141c64..78d6853 100644
--- a/libelf/Makefile.am
+++ b/libelf/Makefile.am
@@ -29,7 +29,7 @@
##
include $(top_srcdir)/config/eu.am
if BUILD_STATIC
-AM_CFLAGS += -fPIC
+AM_CFLAGS += $(fpic_CFLAGS)
endif
GCC_INCLUDE = -I$(shell $(CC) -print-file-name=include)
VERSION = 1
@@ -105,9 +105,9 @@ endif
libelf_so_SOURCES =
libelf.so$(EXEEXT): libelf_pic.a libelf.map
- $(AM_V_CCLD)$(LINK) -shared -o $@ -Wl,--whole-archive,$<,--no-whole-archive \
+ $(AM_V_CCLD)$(LINK) $(dso_LDFLAGS) -o $@ -Wl,--whole-archive,$<,--no-whole-archive \
-Wl,--version-script,$(srcdir)/libelf.map,--no-undefined \
- -Wl,--soname,$@.$(VERSION),-z,defs,-z,relro $(libelf_so_LDLIBS)
+ -Wl,--soname,$@.$(VERSION) $(libelf_so_LDLIBS)
@$(textrel_check)
$(AM_V_at)ln -fs $@ $@.$(VERSION)
diff --git a/libgnu/Makefile.am b/libgnu/Makefile.am
index c4a90e8..0d31e69 100644
--- a/libgnu/Makefile.am
+++ b/libgnu/Makefile.am
@@ -30,7 +30,7 @@
# for eu-config.h
AM_CPPFLAGS = -I$(top_srcdir)/lib
-AM_CFLAGS = -fPIC
+AM_CFLAGS = $(fpic_CFLAGS)
noinst_LIBRARIES =
MOSTLYCLEANFILES =
MOSTLYCLEANDIRS =
diff --git a/tests/ChangeLog b/tests/ChangeLog
index d2a14c2..9d20341 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,5 +1,9 @@
2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+ * Makefile.am: Use fpie_CFLAGS and fpic_CFLAGS.
+
+2017-04-27 Ulf Hermann <ulf.hermann@qt.io>
+
* Makefile.am: Drop argp_LDADD.
* elfstrmerge.c: Don't include system.h.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 69d1fcd..54a99d4 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -468,7 +468,7 @@ dwfl_report_elf_align_LDADD = $(libdw) $(libgnu)
varlocs_LDADD = $(libdw) $(libelf) $(libgnu)
backtrace_LDADD = $(libdw) $(libelf) $(libgnu)
# backtrace-child-biarch also uses those *_CFLAGS and *_LDLAGS variables:
-backtrace_child_CFLAGS = -fPIE
+backtrace_child_CFLAGS = $(fpie_CFLAGS)
backtrace_child_LDFLAGS = -pie -pthread
backtrace_child_biarch_SOURCES = backtrace-child.c
backtrace_data_LDADD = $(libdw) $(libelf) $(libgnu)
@@ -479,7 +479,7 @@ debugaltlink_LDADD = $(libdw) $(libelf) $(libgnu)
buildid_LDADD = $(libdw) $(libelf) $(libgnu)
deleted_LDADD = ./deleted-lib.so $(libgnu)
deleted_lib_so_LDFLAGS = -shared -rdynamic
-deleted_lib_so_CFLAGS = -fPIC -fasynchronous-unwind-tables
+deleted_lib_so_CFLAGS = $(fpic_LDFLAGS) -fasynchronous-unwind-tables
deleted_lib_so_LDADD = $(libgnu)
aggregate_size_LDADD = $(libdw) $(libelf) $(libgnu)
peel_type_LDADD = $(libdw) $(libelf) $(libgnu)
--
2.1.4
reply other threads:[~2017-04-27 15:42 UTC|newest]
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