similar to: [LLVMdev] [MCJIT] Why does it produce non-PIC ELF code?

On 07/08/2011 01:25 PM, Yuri wrote: > ELF that MCJIT writes on x86_64 has relocations in it. Particularly, > R_X86_64_PC32 relocations are used for the sections .gcc_except_table > and .eh_frame related to exception processing. > I am not sure where is general documentation on relocation types, > including R_X86_64_PC32. Looks like it's nowhere to be found on the web. > But

Hi Lang, Yeah, I remember this case. Basically what’s happening is that there are relocations for ELF on x86 that use a value that is present in the object image as part of the calculation for the final value that goes in the same location. If you ever find yourself applying relocations for a second time (for instance, because the loaded object location is remapped for out-of-proc execution)

I would think that the R_X86_64_PC32 relocation type should never be generated with large code model since large code model, by definition, makes no assumptions about the size or address of sections. The use of win32-elf might throw a wrinkle into this, since that is a code path that probably isn't exercised much outside of MCJIT use. That said, when this assertion fails it is usually

Hi llvm-community, I use llc (3.4-final) to generate object file: *llc code.bc -mtriple=x86_64-pc-win32-elf -mcpu=x86-64 -filetype=obj -code-model=large -o=code.o* then I load it with *RuntimeDyld + SectionMemoryManager* in my app. I faced the problem described in 15356 <http://llvm.org/bugs/show_bug.cgi?id=15356>bug. Debug assertion fails at

2010/1/22 Duncan Sands <baldrick at free.fr> > Hi James, > > > I've been trying to get a minimal test function to work, which simply >> invokes _Unwind_RaiseException with a single clean-up landing pad. However. >> when I run it my personality function is not getting called - >> _Unwind_RaiseException simply returns apparently doing nothing. Looking at

Hi James, > I've been trying to get a minimal test function to work, which simply > invokes _Unwind_RaiseException with a single clean-up landing pad. > However. when I run it my personality function is not getting called - > _Unwind_RaiseException simply returns apparently doing nothing. Looking > at the x86-64 assembly output from llc, I can see this is happening >

Compilation failure on c/s 17194 is as follows: /root/randy/vtd-stage/xen/common/built_in.o: In function `guest_remove_page'': /root/randy/vtd-stage/xen/common/memory.c:172: undefined reference to `__bitop_bad_size'' /root/randy/vtd-stage/xen/common/memory.c:172: relocation truncated to fit: R_X86_64_PC32 against undefined symbol `__bitop_bad_size''

Here are the linker errors: lld: warning: libcygwin.a(_cygwin_crt0_common.o): undefined symbol: __data_start__ lld: warning: libcygwin.a(_cygwin_crt0_common.o): undefined symbol: __data_end__ lld: warning: libcygwin.a(_cygwin_crt0_common.o): undefined symbol: __bss_start__ lld: warning: libcygwin.a(_cygwin_crt0_common.o): undefined symbol: __bss_end__ lld: warning:

Hi All, > I think this ignores the real problem with the MCJIT debugging interface: it doesn't give MCJIT clients any way of directly accessing and parsing the debug metadata. Sorry - it wasn't clear from my original post, but I'm hoping to improve debugging APIs in general, not just for the system debugger. I think there are two orthogonal concerns here - (1) the debug info

Hi, Attempting to use LLVM in jitting mode for AMD64, we met a problem. When the jitted routine needs a big stack frame (> 1 page), the system attempts to call __chkstk to probe the stack. This attempt results in assertion in RuntimeDyldELF::resolveX86_64Relocation(), case ELF::R_X86_64_PC32, because the RealOffset does not fit in 32 bits. Same happens with __alloca (when

We need to build with -mno-pic to disable all uses of GP, as well as use a custom linker script to avoid collisions between klibc.so's and the executable's segments. Signed-off-by: James Clarke <jrtc27 at jrtc27.com> --- usr/klibc/arch/ia64/MCONFIG | 3 + usr/klibc/arch/ia64/crt0.S | 4 - usr/klibc/arch/ia64/klibc.ld | 267 ++++++++++++++++++++++++++++++++++++++++++

Commit-ID: 8418552770110e9864ab24d60d8481fac58d3a65 Gitweb: http://git.kernel.org/?p=libs/klibc/klibc.git;a=commit;h=8418552770110e9864ab24d60d8481fac58d3a65 Author: James Clarke <jrtc27 at jrtc27.com> AuthorDate: Mon, 21 Jan 2019 21:26:57 +0000 Committer: Ben Hutchings <ben at decadent.org.uk> CommitDate: Mon, 21 Jan 2019 22:51:27 +0000 [klibc] ia64: Fix shared build We

Hi, I've tracked down what I believe is a bug in lld's relocation processing for R_X86_64_PC32 REL relocations. I'm producing the object file in a slightly unusual way: I'm using objcopy on a relocatable i386 ELF object file to convert it to x86_64 which transforms a R_386_PC32 into a R_X86_64_PC32. Steps to reproduce: 1. Assemble the attached bug.asm using nasm and note the

Hi, I'm in the process of migrating from clang5 to clang10. Unfortunately clang10 introduced a negative performance impact. The cause is an increase of PLT entries from this patch (first released in clang7): https://bugs.llvm.org/show_bug.cgi?id=36370 https://reviews.llvm.org/D43383 If I revert that clang patch locally, the additional PLT entries and the performance impact disappear. This

The following code currently links incorrectly when linking against a dynamic libc on Ubuntu 12.10 unless -fpic is specified. #include <stdio.h> int main() { fputs("hi\n", stdout); } The reason is that stdout gets a R_X86_64_PC32 relocation, but is of type Object. The ELF writer can't see this, and assumes all R_X86_64_PC32 relocations in dynamic outputs are to functions

Is that the only problem to use lld to link cygwin programs? On Thu, Feb 8, 2018 at 8:19 AM, Andrew Kelley <superjoe30 at gmail.com> wrote: > Here are the linker errors: > > lld: warning: libcygwin.a(_cygwin_crt0_common.o): undefined symbol: > __data_start__ > lld: warning: libcygwin.a(_cygwin_crt0_common.o): undefined symbol: > __data_end__ > lld: warning:

Hi, I'm trying to get exception handling working in my compiler targetting LLVM. I've been working from the LLVM exception handling documentation (including http://llvm.org/docs/ExceptionHandling.html and http://wiki.llvm.org/HowTo:_Build_JIT_based_Exception_mechanism) and looking at g++-llvm's output. I've been trying to get a minimal test function to work, which simply invokes

Hello, Bjarke > * Provide a pass that raises C++ exception handling to just > unwind instructions and thread-local data. Are you familiar with C++ EH? How would you handle catches? Cleanups? > Other call frames might be more complex to handle. It depends on the > moves needed to restore the registers of the previous call frame (the > caller) and to remove the current frame.

This should fix this warning from Visual Studio 2010: 33>..\..\..\llvm-2.8svn-build\lib\MC\MachObjectWriter.cpp(772): warning C4334: '<<' : result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?) Index: lib/MC/MachObjectWriter.cpp =================================================================== --- lib/MC/MachObjectWriter.cpp (revision 111120) +++

On Sep 23, 2013, at 4:52 PM, Michael Spencer <bigcheesegs at gmail.com> wrote: > The following code currently links incorrectly when linking against a dynamic libc on Ubuntu 12.10 unless -fpic is specified. > > #include <stdio.h> > > int main() { > fputs("hi\n", stdout); > } > > The reason is that stdout gets a R_X86_64_PC32 relocation, but is