[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 Isa Bella changed: What|Removed |Added CC||bisa25018 at gmail dot com --- Comment #17 from Isa Bella --- Hey, I am a content writer, magazine publisher, and technical blogger currently living in San Diego, CA, USA. My interests range from antivirus to McAfee. Visit:- https://mcafee-activate.uk.net/ https://norton-setup.uk.net/ https://www-office-setup.uk.net/ https://infonorton.com/ -- You are receiving this mail because: You are on the CC list for the bug.
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #16 from Nick Clifton --- Created attachment 12014 --> https://sourceware.org/bugzilla/attachment.cgi?id=12014=edit Another patch Hi Guys, Sorry for dropping the ball on this one. I have now applied a slight variation on Niklas's second patch, with a little bit of code tidying and the addition of a test case. I have applied the patch to the mainline and the 2.33 branch, but the patch might not be in the official 2.33 release, if the release tarballs have already been made. Cheers Nick -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #15 from cvs-commit at gcc dot gnu.org --- The binutils-2_33-branch branch has been updated by Nick Clifton : https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=146a3bb9cc78c459e63c23259d766b01c32df705 commit 146a3bb9cc78c459e63c23259d766b01c32df705 Author: Nick Clifton Date: Wed Oct 2 11:57:16 2019 +0100 Change objcopy's --set-section-alignment option so that it takes a byte alignment value rather than a power of two alignment value. PR 24942 * objcopy.c (copy_usage): Update description of --set-section-alignment. (copy_main): Interpret numeric argument of --set-section-alignment as a byte alignment, not a power of two alignment. * doc/binutils.texi: Update description of --set-section-alignment. * testsuite/binutils-all/set-section-alignment.d: New test. * testsuite/binutils-all/objcopy.exp: Run the new test. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #14 from cvs-commit at gcc dot gnu.org --- The master branch has been updated by Nick Clifton : https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=de4859eacb74a440d9fd61e4a0f051e3737a05dd commit de4859eacb74a440d9fd61e4a0f051e3737a05dd Author: Nick Clifton Date: Wed Oct 2 11:55:02 2019 +0100 Change objcopy's --set-section-alignment option to take a byte alignment value rather than a power of two alignment value. PR 24942 * objcopy.c (copy_usage): Update description of --set-section-alignment. (copy_main): Interpret numeric argument of --set-section-alignment as a byte alignment, not a power of two alignment. * doc/binutils.texi: Update description of --set-section-alignment. * testsuite/binutils-all/set-section-alignment.d: New test. * testsuite/binutils-all/objcopy.exp: Run the new test. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #13 from Fangrui Song --- Ping:) FWIW, I have a patch to implement --set-section-alignment in llvm-objcopy https://reviews.llvm.org/D67656 . I don't want to cause gratuitous differences from GNU objcopy, so I haven't committed that change yet. At least two other people there think that specifying the raw value (instead of the exponent) is more intuitive. A commitment from the binutils side that the two tools will be in agreement (with the release of binutils 2.33) is all what I need to proceed with that change. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #12 from Fangrui Song --- > Created attachment 12002 [details] if (palign <= 0 || palign & (palign-1)) can be used to simplify the code. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #11 from Niklas Gürtler --- Created attachment 12002 --> https://sourceware.org/bugzilla/attachment.cgi?id=12002=edit Patch for specifying powers of two instead of exponents Okay, here is a patch for specifying the alignment as a power of two instead of an exponent. I don't like it very much however... -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 James Henderson changed: What|Removed |Added CC||jh7370 at my dot bristol.ac.uk --- Comment #10 from James Henderson --- I'm with Fangrui on this one. Although I don't know of any instances of non-powers-of-2 alignment making sense, I still talk about an alignment of, say, 4, as "4" not "2". Similarly, tools print alignment as the actual value, not as a power of 2, in my experience. As such, I expect switches to conform to that. Indeed, as pointed out, that's exactly what .align does on many platforms, and also every tool I've ever used that has anything to do with alignment (in fact, I didn't even know .align had a different behaviour on some platforms). Additionally, I think it's much more likely that a user who hasn't looked in depth at the documentation will try to specify the raw value, and then will end up with an incorrect modification, than the other way around. Furthermore, it is simpler for a user to not have to do the conversion of, say, 128 to 2 to the whatever. If bfd can't support non-powers-of-2 alignment values, it should simply reject them at command-line parsing time, in my opinion. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #9 from Fangrui Song --- I don't require the support for non power-of-2 alignment. I just want to say --set-section-alignment .foo=8 => sh_addralign=256 is counterintuitive. It is not what readelf -S displays. (objdump -h displays it as `2**8`. The `**` at least makes it clear that an exponent is involved.) > I think not all BFD targets support arbitrary alignment, some may only > support powers of 2. We can simply reject non power-of-2 alignment when parsing the command line option, like what you've done when there is no string on the right of `=` > The ".align" directive also works this way (at least on ARM). I know that the .align directive is in powers of 2 on ARM/AArch64/MIPS/PowerPC, but it is in bytes on x86, Sparc and System z. I don't know how this inconsistency came, .balign and .p2align may be better. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #8 from Niklas Gürtler --- I think not all BFD targets support arbitrary alignment, some may only support powers of 2. The internal representation in the BFD library stores only the exponent, so there would have to be a conversion (i.e. log2), with additional potential for errors, so I think it's best to have the user do that and document it properly. The ".align" directive also works this way (at least on ARM). When using --rename-section, the original section name would need to be specified for --set-section-alignment, just like with --set-section-flags. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #7 from Fangrui Song --- In addition, have you thought about its interaction with --rename-section? Which command should I use: objcopy --rename-section=.foo=.foo2 --set-section-alignment .foo=8 a.o b.o or objcopy --rename-section=.foo=.foo2 --set-section-alignment .foo2=8 a.o b.o -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942
Fangrui Song changed:
What|Removed |Added
CC||maskray at google dot com
--- Comment #6 from Fangrui Song ---
+@item --set-section-alignment @var{sectionpattern}=@var{align}
+Set the alignment for any sections matching @var{sectionpattern}. @var{align}
+specifies the alignment as the exponent for the power of two, i.e. the
+alignment in bytes will be 2^@var{align}.
objcopy -I binary -B i386:x86-64 -O elf64-x86-64 --set-section-alignment
.data=8 a.txt a.o
I would expect the alignment of .data to be 8, instead of 256. Specifying the
exponent for the power of two may be awkward, I hope you can change this.
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[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #5 from Niklas Gürtler --- Hi Nick, awesome, thank you! Now just to wait for the release... :) Have a nice day, Niklas -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 Nick Clifton changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|--- |FIXED --- Comment #4 from Nick Clifton --- Hi Niklas, Very well, since the patch is simple enough to count as obvious, I have gone ahead and applied it. Cheers Nick -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #3 from cvs-commit at gcc dot gnu.org --- The master branch has been updated by Nick Clifton : https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=fa463e9fc644e7a3bad39aa73bf6be72ea865805 commit fa463e9fc644e7a3bad39aa73bf6be72ea865805 Author: Niklas G?rtler Date: Wed Aug 28 12:33:41 2019 +0100 Add an option to objcopy to change the alignment of sections. PR 24942 * objcopy.c (SECTION_CONTEXT_SET_ALIGNMENT): New constant. (struct section_list): Add alignment field. (command_line_switch): Add OPTION_SET_SECTION_ALIGNMENT. (copy_options): Add --set-section-alignment. (copy_usage): Describe --set-section-alignment. (find_section_list): Initialise the alignment field. (setup_section): Handle the alignment field. (copy_main): Handle OPTION_SET_SECTION_ALIGNMENT. * doc/binutils.texi: Document the new feature. * NEWS: Mention the new feature. -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 --- Comment #2 from Niklas Gürtler --- Hi Nick, I knew about "incbin" but needing an (additional) assembly file seems somewhat clunky. There are even more possibilities: Putting each converted .o file into its own section, and aligning those sections via the final linker script. Hacking together a tool that modifies the alignment field in the ELF header. It might even be possible to do a partial linking step to set the alignment of a objcopy-produced .o-file using a linker script. However, if objcopy is capable of converting binary to ELF, then why not make it actually useful by setting the alignment requirement, especially since it's a rather simple fix? This would allow us to produce the desired .o file with one simple step. Greetings, Niklas -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
[Bug binutils/24942] objcopy: Add option for setting section alignment
https://sourceware.org/bugzilla/show_bug.cgi?id=24942 Nick Clifton changed: What|Removed |Added CC||nickc at redhat dot com --- Comment #1 from Nick Clifton --- Hi Niklas, There is an easier way of solving this problem - the assembler's .incbin directive. For example: % cat foo.s .section foo-image, "a", @progbits .align 4 .global start_of_foo start_of_foo: .incbin "foo.jpg" .global end_of_foo end_of_foo: Assembling this will create an object file called foo.o which contains the contents of foo.jpg in a section called foo-image, and which is aligned to 4 bytes. Cheers Nick -- You are receiving this mail because: You are on the CC list for the bug. ___ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
