| Message ID | 1625902.vd5h90ZESU@laptop1.gw.ume.nu |
|---|---|
| State | New |
| Headers | show |
On 31/12/14 07:23, Magnus Granberg wrote: > fredag 14 november 2014 23.31.48 skrev Magnus Granberg: >> måndag 10 november 2014 21.26.39 skrev Magnus Granberg: >>>> Rainer >>> >>> Thanks Rainer for the nits and comments. >>> Have updated the patches and Changelogs. >>> But i still use PIE_DRIVER_SELF_SPECS, do you have a ide where move it so >>> i don't need to duplicate that stuff or how to do it? >>> >>> Magnus G >>> >>> 2014-11-10 Magnus Granberg <zorry@gentoo.org> >>> >>> /gcc >>> * config/gnu-user.h (PIE_DRIVER_SELF_SPECS) and >>> (GNU_DRIVER_SELF_SPECS): Define. >>> * config/i386/gnu-user-common.h (DRIVER_SELF_SPECS): Define >>> * configure.ac: Add new option. >>> * configure, config.in: Rebuild. >>> * Makefile.in (ALL_CFLAGS) and (ALL_CXXFLAGS): Disable PIE. >>> * doc/install.texi: New configure option. >>> * doc/invoke.texi: Add note to PIE. >>> * doc/sourcebuild.texi: New effective target. >>> gcc/testsuite >>> * gcc/default-pie.c: New test >>> * gcc.dg/tree-ssa/ssa-store-ccp-3.c: Skip if default_pie >>> * g++.dg/other/anon5.C: Skip if default_pie >>> * lib/target-supports.exp (check_effective_target_default_pie): >>> New proc. >>> /libgcc >>> * Makefile.in (CRTSTUFF_CFLAGS): Disable PIE. >> >> Can this be included for GCC 5 ? >> >> /Magnus G. > One more ping on this. The patches where sent before stage 1 closed but i > did't get any feed back from it > Have updete the patchses for gcc 5.0 20141228 snapshot. > Bootstrapped and tested on x86_64-unknown-linux-gnu (Gentoo) > /Magnus > I'm giving this a further ping as my distribution has interest in these patches. Thanks! > 2014-12-30 Magnus Granberg <zorry@gentoo.org> > > /gcc > * config/gnu-user.h (PIE_DRIVER_SELF_SPECS): Define. > * config/i386/gnu-user-common.h (DRIVER_SELF_SPECS): Define and > add PIE_DRIVER_SELF_SPECS. > * configure.ac: Add new option. > * configure, config.in: Rebuild. > * Makefile.in (ALL_CFLAGS) and (ALL_CXXFLAGS): Disable PIE. > * doc/install.texi: New configure option. > * doc/invoke.texi: Add note to PIE. > * doc/sourcebuild.texi: New effective target. > gcc/testsuite > * gcc/default-pie.c: New test > * gcc.dg/tree-ssa/ssa-store-ccp-3.c: Skip if default_pie > * g++.dg/other/anon5.C: Skip if default_pie > * lib/target-supports.exp (check_effective_target_default_pie): > New proc. > /libgcc > * Makefile.in (CRTSTUFF_CFLAGS): Disable PIE. >
On Tue, Dec 30, 2014 at 10:23 PM, Magnus Granberg <zorry@gentoo.org> wrote: > fredag 14 november 2014 23.31.48 skrev Magnus Granberg: >> måndag 10 november 2014 21.26.39 skrev Magnus Granberg: >> > > Rainer >> > >> > Thanks Rainer for the nits and comments. >> > Have updated the patches and Changelogs. >> > But i still use PIE_DRIVER_SELF_SPECS, do you have a ide where move it so >> > i don't need to duplicate that stuff or how to do it? >> > >> > Magnus G >> > >> > 2014-11-10 Magnus Granberg <zorry@gentoo.org> >> > >> > /gcc >> > * config/gnu-user.h (PIE_DRIVER_SELF_SPECS) and >> > (GNU_DRIVER_SELF_SPECS): Define. >> > * config/i386/gnu-user-common.h (DRIVER_SELF_SPECS): Define >> > * configure.ac: Add new option. >> > * configure, config.in: Rebuild. >> > * Makefile.in (ALL_CFLAGS) and (ALL_CXXFLAGS): Disable PIE. >> > * doc/install.texi: New configure option. >> > * doc/invoke.texi: Add note to PIE. >> > * doc/sourcebuild.texi: New effective target. >> > gcc/testsuite >> > * gcc/default-pie.c: New test >> > * gcc.dg/tree-ssa/ssa-store-ccp-3.c: Skip if default_pie >> > * g++.dg/other/anon5.C: Skip if default_pie >> > * lib/target-supports.exp (check_effective_target_default_pie): >> > New proc. >> > /libgcc >> > * Makefile.in (CRTSTUFF_CFLAGS): Disable PIE. >> >> Can this be included for GCC 5 ? >> >> /Magnus G. > One more ping on this. The patches where sent before stage 1 closed but i > did't get any feed back from it > Have updete the patchses for gcc 5.0 20141228 snapshot. > Bootstrapped and tested on x86_64-unknown-linux-gnu (Gentoo) > /Magnus Looking at the actual implementation I wonder why it's not similar to how darwin gets at it default (not sure how it does). Also looking at how DRIVER_SELF_SPECS is used I wonder if the functionality can be enabled with a simple --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE|shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE -pie}" at configure time (using CONFIGURE_SPECS). I have no idea if the above is really the proper spec to use - why do you include static, nostdlib, nodefaultlibs and nostartfiles for example? Similar, if I say gcc -pie -c t.c we will end up with a non-PIE object, and linking with -fPIE will end up with a DYN_EXEC object. I believe you want to treat link and compile arguments separately (and adjust the link spec for linking). I also would have said that elfos.h is more appropriate than gnu-user.h, but ... That said, the patch looks more like a hack (and see above how to achieve the same without a patch(?)), not like a proper implementation of a PIE default. Joseph may have an idea where the proper place for a spec-wise default PIE is. Thanks, Richard. > 2014-12-30 Magnus Granberg <zorry@gentoo.org> > > /gcc > * config/gnu-user.h (PIE_DRIVER_SELF_SPECS): Define. > * config/i386/gnu-user-common.h (DRIVER_SELF_SPECS): Define and > add PIE_DRIVER_SELF_SPECS. > * configure.ac: Add new option. > * configure, config.in: Rebuild. > * Makefile.in (ALL_CFLAGS) and (ALL_CXXFLAGS): Disable PIE. > * doc/install.texi: New configure option. > * doc/invoke.texi: Add note to PIE. > * doc/sourcebuild.texi: New effective target. > gcc/testsuite > * gcc/default-pie.c: New test > * gcc.dg/tree-ssa/ssa-store-ccp-3.c: Skip if default_pie > * g++.dg/other/anon5.C: Skip if default_pie > * lib/target-supports.exp (check_effective_target_default_pie): > New proc. > /libgcc > * Makefile.in (CRTSTUFF_CFLAGS): Disable PIE. >
On 09/01/15 07:58 AM, Richard Biener wrote: > > Looking at the actual implementation I wonder why it's not similar > to how darwin gets at it default (not sure how it does). Also > looking at how DRIVER_SELF_SPECS is used I wonder if the > functionality can be enabled with a simple > > --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE|shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE > -pie}" > > at configure time (using CONFIGURE_SPECS). > > I have no idea if the above is really the proper spec to use - why > do you include static, nostdlib, nodefaultlibs and nostartfiles > for example? Similar, if I say PIE isn't supported for static executables by binutils, etc. so it does need to exclude that. The checks for nostdlib, nodefaultlibs and nostartfiles do seem unnecessary. I think distributions include those in the existing wrapper scripts and GCC patches because it avoids the need for patching build systems for kernel / freestanding code to include -fno-pie, but it's more correct to leave these out. > gcc -pie -c t.c > > we will end up with a non-PIE object, and linking with -fPIE will > end up with a DYN_EXEC object. > > I believe you want to treat link and compile arguments separately > (and adjust the link spec for linking). I also would have said that > elfos.h is more appropriate than gnu-user.h, but ... Handling it separately is what the existing wrapper scripts for this do: -fno-PIC|-fno-pic|-fno-PIE|-fno-pie|-static|--static|-shared|--shared) force_fPIE=0 force_pie=0 ;; -fPIC|-fpic|-fPIE|-fpie) force_fPIE=0 ;; -c|-E|-S) force_pie=0 ;; I think it's appropriate for it to > That said, the patch looks more like a hack (and see above how > to achieve the same without a patch(?)), not like a proper implementation > of a PIE default. I don't think it can be considered a hack if it's handling all of the cases correctly, so it might need some changes from the current implementation but that doesn't make it a dead end. Is it actually done in a significantly different way for OS X? If it can be done by passing --with-specs to configure then that could be a viable alternative for distributions that do not want to add GCC patches or use wrapper scripts (Arch Linux) but I'm not sure that it will fly.
On Fri, 9 Jan 2015, Daniel Micay wrote: > > --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE|shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE > > -pie}" > > > > at configure time (using CONFIGURE_SPECS). > > > > I have no idea if the above is really the proper spec to use - why > > do you include static, nostdlib, nodefaultlibs and nostartfiles > > for example? Similar, if I say > > PIE isn't supported for static executables by binutils, etc. so it > does need to exclude that. The checks for nostdlib, nodefaultlibs Well - that would indicate excluding -pie if one of the link-time options conflicting with it is used, -fPIE if one of the compile-time options conflicting with it is used. That way, "gcc -static file.c" would still have the same effect as "gcc -c file.c; gcc -static file.o" (building a PIE object, linking it into a non-PIE static executable), which makes logical sense to me (although there may be no great benefit either way).
On 09/01/15 12:49 PM, Joseph Myers wrote: > On Fri, 9 Jan 2015, Daniel Micay wrote: > >>> --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE|shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE >>> -pie}" >>> >>> at configure time (using CONFIGURE_SPECS). >>> >>> I have no idea if the above is really the proper spec to use - why >>> do you include static, nostdlib, nodefaultlibs and nostartfiles >>> for example? Similar, if I say >> >> PIE isn't supported for static executables by binutils, etc. so it >> does need to exclude that. The checks for nostdlib, nodefaultlibs > > Well - that would indicate excluding -pie if one of the link-time options > conflicting with it is used, -fPIE if one of the compile-time options > conflicting with it is used. That way, "gcc -static file.c" would still > have the same effect as "gcc -c file.c; gcc -static file.o" (building a > PIE object, linking it into a non-PIE static executable), which makes > logical sense to me (although there may be no great benefit either way). Sure, I agree. It should have separate lists of exceptions for both of these.
fredag 09 januari 2015 13.00.14 skrev Daniel Micay: > On 09/01/15 12:49 PM, Joseph Myers wrote: > > On Fri, 9 Jan 2015, Daniel Micay wrote: > >>> --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE| > >>> shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE -pie}" > >>> > >>> at configure time (using CONFIGURE_SPECS). DRIVER_SELF_SPECS is checkt before CONFIGURE_SPECS. On mips it will have added -mno-shared before it check CONFIGURE_SPECS. I want to support more targets later on. Can move the spec to elfos.h. > >>> > >>> I have no idea if the above is really the proper spec to use - why > >>> do you include static, nostdlib, nodefaultlibs and nostartfiles > >>> for example? Similar, if I say > >> > >> PIE isn't supported for static executables by binutils, etc. so it > >> does need to exclude that. The checks for nostdlib, nodefaultlibs > > > > Well - that would indicate excluding -pie if one of the link-time options > > conflicting with it is used, -fPIE if one of the compile-time options > > conflicting with it is used. That way, "gcc -static file.c" would still > > have the same effect as "gcc -c file.c; gcc -static file.o" (building a > > PIE object, linking it into a non-PIE static executable), which makes > > logical sense to me (although there may be no great benefit either way). > > Sure, I agree. It should have separate lists of exceptions for both of > these. I can separete it to compile and linke sections and remove the nostdlib, nodefaultlibs and nostartfiles. But how do we not pass -pie to the linker when we don't pass static or shared and don't link it with -pie? For only the gold linker support -no-pie. /Magnus G.
On Fri, Jan 9, 2015 at 12:12 PM, Magnus Granberg <zorry@gentoo.org> wrote: > fredag 09 januari 2015 13.00.14 skrev Daniel Micay: >> On 09/01/15 12:49 PM, Joseph Myers wrote: >> > On Fri, 9 Jan 2015, Daniel Micay wrote: >> >>> --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE| >> >>> shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE -pie}" >> >>> >> >>> at configure time (using CONFIGURE_SPECS). > DRIVER_SELF_SPECS is checkt before CONFIGURE_SPECS. On mips it will have added > -mno-shared before it check CONFIGURE_SPECS. I want to support more targets > later on. Can move the spec to elfos.h. >> >>> >> >>> I have no idea if the above is really the proper spec to use - why >> >>> do you include static, nostdlib, nodefaultlibs and nostartfiles >> >>> for example? Similar, if I say >> >> >> >> PIE isn't supported for static executables by binutils, etc. so it >> >> does need to exclude that. The checks for nostdlib, nodefaultlibs >> > >> > Well - that would indicate excluding -pie if one of the link-time options >> > conflicting with it is used, -fPIE if one of the compile-time options >> > conflicting with it is used. That way, "gcc -static file.c" would still >> > have the same effect as "gcc -c file.c; gcc -static file.o" (building a >> > PIE object, linking it into a non-PIE static executable), which makes >> > logical sense to me (although there may be no great benefit either way). >> >> Sure, I agree. It should have separate lists of exceptions for both of >> these. > I can separete it to compile and linke sections and remove the nostdlib, > nodefaultlibs and nostartfiles. But how do we not pass -pie to the linker when > we don't pass static or shared and don't link it with -pie? For only the gold > linker support -no-pie. > > /Magnus G. > > Please try hjl/pie branch: https://gcc.gnu.org/git/?p=gcc.git;a=summary and let know if it works for you.
On Fri, Jan 9, 2015 at 5:56 PM, H.J. Lu <hjl.tools@gmail.com> wrote: > On Fri, Jan 9, 2015 at 12:12 PM, Magnus Granberg <zorry@gentoo.org> wrote: >> fredag 09 januari 2015 13.00.14 skrev Daniel Micay: >>> On 09/01/15 12:49 PM, Joseph Myers wrote: >>> > On Fri, 9 Jan 2015, Daniel Micay wrote: >>> >>> --with-specs="%{pie|fpic|fPIC|fpie|fPIE|fno-pic|fno-PIC|fno-pie|fno-PIE| >>> >>> shared|static|nostdlib|nodefaultlibs|nostartfiles:;:-fPIE -pie}" >>> >>> >>> >>> at configure time (using CONFIGURE_SPECS). >> DRIVER_SELF_SPECS is checkt before CONFIGURE_SPECS. On mips it will have added >> -mno-shared before it check CONFIGURE_SPECS. I want to support more targets >> later on. Can move the spec to elfos.h. >>> >>> >>> >>> I have no idea if the above is really the proper spec to use - why >>> >>> do you include static, nostdlib, nodefaultlibs and nostartfiles >>> >>> for example? Similar, if I say >>> >> >>> >> PIE isn't supported for static executables by binutils, etc. so it >>> >> does need to exclude that. The checks for nostdlib, nodefaultlibs >>> > >>> > Well - that would indicate excluding -pie if one of the link-time options >>> > conflicting with it is used, -fPIE if one of the compile-time options >>> > conflicting with it is used. That way, "gcc -static file.c" would still >>> > have the same effect as "gcc -c file.c; gcc -static file.o" (building a >>> > PIE object, linking it into a non-PIE static executable), which makes >>> > logical sense to me (although there may be no great benefit either way). >>> >>> Sure, I agree. It should have separate lists of exceptions for both of >>> these. >> I can separete it to compile and linke sections and remove the nostdlib, >> nodefaultlibs and nostartfiles. But how do we not pass -pie to the linker when >> we don't pass static or shared and don't link it with -pie? For only the gold >> linker support -no-pie. >> >> /Magnus G. >> >> > > Please try hjl/pie branch: > > https://gcc.gnu.org/git/?p=gcc.git;a=summary > > and let know if it works for you. > I updated the branch with some fixes.
--- a/gcc/testsuite/gcc.dg/default-pie.c 2013-11-09 21:07:16.741479728 +0100 +++ b/gcc/testsuite/gcc.dg/default-pie.c 2013-11-09 21:05:07.801479218 +0100 @@ -0,0 +1,11 @@ +/* { dg-require-effective-target default_pie } */ +/* { dg-options "-O2" } */ +int foo (void); + +int +main (void) +{ + return foo (); +} + +/* { dg-final { scan-assembler "foo@PLT" } } */ --- a/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c 2012-03-14 17:33:37.000000000 +0100 +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c 2014-07-29 00:55:17.421086416 +0200 @@ -2,6 +2,7 @@ /* Skipped on MIPS GNU/Linux target because __PIC__ can be defined for executables as well as shared libraries. */ /* { dg-skip-if "" { *-*-darwin* hppa*64*-*-* mips*-*-linux* *-*-mingw* } { "*" } { "" } } */ +/* { dg-skip-if "" { default_pie } { "*" } { "" } } */ /* { dg-options "-O2 -fno-common -fdump-tree-optimized" } */ const int conststaticvariable; --- a/gcc/testsuite/g++.dg/other/anon5.C 2012-11-10 15:34:42.000000000 +0100 +++ b/gcc/testsuite/g++.dg/other/anon5.C 2013-11-09 14:49:52.281390127 +0100 @@ -1,5 +1,6 @@ // PR c++/34094 // { dg-do link { target { ! { *-*-darwin* *-*-hpux* *-*-solaris2.* } } } } +// { dg-skip-if "" { default_pie } { "*" } { "" } } // { dg-options "-g" } // Ignore additional message on powerpc-ibm-aix // { dg-prune-output "obtain more information" } */ --- a/gcc/testsuite/lib/target-supports.exp 2013-10-01 11:18:30.000000000 +0200 +++ b/gcc/testsuite/lib/target-supports.exp 2013-10-25 22:01:46.743388469 +0200 @@ -475,6 +475,11 @@ proc check_profiling_available { test_wh } } + # Profiling doesn't work with default -fPIE -pie. + if { [check_effective_target_default_pie] } { + return 0 + } + # Support for -p on solaris2 relies on mcrt1.o which comes with the # vendor compiler. We cannot reliably predict the directory where the # vendor compiler (and thus mcrt1.o) is installed so we can't @@ -927,6 +927,14 @@ proc check_effective_target_pie { } { return 0 } +# Return 1 if -pie, -fPIE are enable by default, 0 otherwise. + +proc check_effective_target_default_pie { } { + global ENABLE_DEFAULT_PIE + return [info exists ENABLE_DEFAULT_PIE] + return 0 +} + # Return true if the target supports -mpaired-single (as used on MIPS). proc check_effective_target_mpaired_single { } {