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This is something I discovered when working on aarch64, though it's relevant to x86_64 too. The PE32+ imports are located in the .idata section, which starts off with a 20-byte structure for each DLL, containing offsets into the rest of the section. This is the Import Directory Table in https://learn.microsoft.com/en-us/windows/win32/debug/pe-format, which is a concatenation of the .idata$2 sections. This is then followed by an 20 zero bytes generated by the linker script, which calls this .idata$3. After this comes the .idata$4 entries for each function, which the loader overwrites with the function pointers. Because there's no padding between .idata$3 and .idata$4, this means that if there's an even number of DLLs, the function pointers won't be aligned on an 8-byte boundary. Misaligned reads are slower on x86_64, but this is more important on aarch64, as the e.g. `ldr x0, [x0, :lo12:__imp__func]` the compiler might generate requires __imp__func (the .idata$4 entry) to be aligned to 8 bytes. Without this you get IMAGE_REL_ARM64_PAGEOFFSET_12L overflow errors.
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.