src/libexec/rtld-elf/debug.h, branch releng/12.4

MFC r346216:

2019-04-21T09:11:22Z

ld-elf.so: make LD_DEBUG always functional.

libexec: adoption of SPDX licensing ID tags.

2017-11-27T15:25:02Z

Mainly focus on files that use BSD 2-Clause license, however the tool I was using misidentified many licenses so this was mostly a manual - error prone - task. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts. No functional change intended.

Remove historical GNUC test

2015-05-06T15:29:11Z

The requirement is for a GCC-compatible compiler and not necessarily GCC itself. However, we currently expect any compiler used for building the whole of FreeBSD to be GCC-compatible and many things will break if not; there's no longer a need to have an explicit test for this in rtld. Reviewed by: imp, kib Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D2422

Use C99's varadic macro syntax instead of gcc's.

2006-03-28T18:26:47Z

Add initial support for compiling a special 32 bit version of

2004-03-21T01:21:26Z

ld-elf.so.1 on 64 bit systems. Most of this involves using alternate paths, environment variables and diagnostic messages. The build glue is seperate.

Use STD{ERR,IN,OUT}_FILENO instead of their numeric values. The

2001-07-26T11:02:39Z

definitions are more readable, and it's possible that they're more portable to pathalogical platforms. Submitted by: David Hill

Add a new function dllockinit() for registering thread locking

1999-12-27T04:44:04Z

functions to be used by the dynamic linker. This can be called by threads packages at start-up time. I will add the call to libc_r soon. Also add a default locking method that is used up until dllockinit() is called. The default method works by blocking SIGVTALRM, SIGPROF, and SIGALRM in critical sections. It is based on the observation that most user-space threads packages implement thread preemption with one of these signals (usually SIGVTALRM). The dynamic linker has never been reentrant, but it became less reentrant in revision 1.34 of "src/libexec/rtld-elf/rtld.c". Starting with that revision, multiple threads each doing lazy binding could interfere with each other. The usual symptom was that a symbol was falsely reported as undefined at start-up time. It was rare but not unseen. This commit fixes it.

Enable -Wformat checking for debug_printf().

1999-09-04T20:36:27Z

$Id$ -> $FreeBSD$

1999-08-28T00:22:10Z

Import the ELF dynamic linker. This is the ElfKit version with

1998-03-07T19:24:35Z

quite a few enhancements and bug fixes. There are still some known deficiencies, but it should be adequate to get us started with ELF. Submitted by: John Polstra