push to stable (#1960)

* Output afl-clang-fast stuffs only if necessary (#1912)

* afl-cc header

* afl-cc common declarations

 - Add afl-cc-state.c
 - Strip includes, find_object, debug/be_quiet/have_*/callname setting from afl-cc.c
 - Use debugf_args in main
 - Modify execvp stuffs to fit new aflcc struct

* afl-cc show usage

* afl-cc mode selecting

1. compiler_mode by callname in argv[0]
2. compiler_mode by env "AFL_CC_COMPILER"
3. compiler_mode/instrument_mode by command line options "--afl-..."
4. instrument_mode/compiler_mode by various env vars including "AFL_LLVM_INSTRUMENT"
5. final checking steps
6. print "... - mode: %s-%s\n"
7. determine real argv[0] according to compiler_mode

* afl-cc macro defs

* afl-cc linking behaviors

* afl-cc fsanitize behaviors

* afl-cc misc

* afl-cc body update

* afl-cc all-in-one

formated with custom-format.py

* nits

---------

Co-authored-by: vanhauser-thc <vh@thc.org>

* changelog

* update grammar mutator

* lto llvm 12+

* docs(custom_mutators): fix missing ':' (#1953)

* Fix broken LTO mode and response file support (#1948)

* Strip `-Wl,-no-undefined` during compilation (#1952)

Make the compiler wrapper stripping `-Wl,-no-undefined` in addition to `-Wl,--no-undefined`.
Both versions of the flag are accepted by clang and, therefore, used by building systems in the wild (e.g., samba will not build without this fix).

* Remove dead code in write_to_testcase (#1955)

The custom_mutators_count check in if case is duplicate with if condition.
The else case is custom_mutators_count == 0, neither custom_mutator_list iteration nor sent check needed.

Signed-off-by: Xeonacid <h.dwwwwww@gmail.com>

* update qemuafl

* WIP: Add ability to generate drcov trace using QEMU backend (#1956)

* Document new drcov QEMU plugin

* Add link to lightkeeper for QEMU drcov file loading

---------

Co-authored-by: Jean-Romain Garnier <jean-romain.garnier@airbus.com>

* code format

* changelog

* sleep on uid != 0 afl-system-config

* fix segv about skip_next, warn on unsupported cases of linking options (#1958)

* todos

* ensure afl-cc only allows available compiler modes

* update grammar mutator

* disable aslr on apple

* fix for arm64

---------

Signed-off-by: Xeonacid <h.dwwwwww@gmail.com>
Co-authored-by: Sonic <50692172+SonicStark@users.noreply.github.com>
Co-authored-by: Xeonacid <h.dwwwwww@gmail.com>
Co-authored-by: Nils Bars <nils.bars@rub.de>
Co-authored-by: Jean-Romain Garnier <7504819+JRomainG@users.noreply.github.com>
Co-authored-by: Jean-Romain Garnier <jean-romain.garnier@airbus.com>

GNUmakefile.llvm

@@ -51,7 +51,7 @@ LLVM_TOO_OLD = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^[1-9]
 LLVM_NEW_API = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[0-9]' && echo 1 || echo 0 )
 LLVM_NEWER_API = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[6-9]' && echo 1 || echo 0 )
 LLVM_13_OK = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[3-9]' && echo 1 || echo 0 )
-LLVM_HAVE_LTO = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[1-9]' && echo 1 || echo 0 )
+LLVM_HAVE_LTO = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[2-9]' && echo 1 || echo 0 )
 LLVM_BINDIR = $(shell $(LLVM_CONFIG) --bindir 2>/dev/null)
 LLVM_LIBDIR = $(shell $(LLVM_CONFIG) --libdir 2>/dev/null)
 LLVM_STDCXX = gnu++11
@@ -95,12 +95,12 @@ ifeq "$(LLVM_NEWER_API)" "1"
 endif
 
 ifeq "$(LLVM_HAVE_LTO)" "1"
-  $(info [+] llvm_mode detected llvm 11+, enabling afl-lto LTO implementation)
+  $(info [+] llvm_mode detected llvm 12+, enabling afl-lto LTO implementation)
   LLVM_LTO = 1
 endif
 
 ifeq "$(LLVM_LTO)" "0"
-  $(info [+] llvm_mode detected llvm < 11, afl-lto LTO will not be build.)
+  $(info [+] llvm_mode detected llvm < 12, afl-lto LTO will not be build.)
 endif
 
 ifeq "$(LLVM_APPLE_XCODE)" "1"