add -Wbidirectional patch (#2008391)

fix mangling of lambdas in default args (PR c++/91241, #1981822)
add a few Provides: bundled

revert upstream PR85873 gcc-8 fix, apply the fix from gcc-9 (#1960701)
fix 'this' adjustment for devirtualized call (PR c++/100797, #1965951)

update from GCC 8.5 release (#1946758)
this includes a fix for PR target/87839 (#1958295)

remove support for demangling GCC 2.x era mangling schemes (#1668394)

update from GCC 8.4 release (#1946758)

back out the PR97236 patch

fix bad use of VMAT_CONTIGUOUS (PR tree-optimization/97236, #1925632)

update from GCC 8.4 release (#1868446)
remove symlinks to 32-bit versions of these static libraries: libasan.a,

backport aarch64 LSE atomics (#1821994)

consider negative edges in cycle detection (#1817991, PR gcov-profile/91601)
fix Fortran debug info for arrays with descriptors (#1655624,
fix wrong code emitted for movv1qi on s390x (#1784758, PR target/92950)

update from Fedora gcc-8.3.1-5 (#1747157)
use unspec_volatile for darn (PR target/91481, #1760205, CVE-2019-15847)

fix shift count operand printing (#1730380)
fix tree-outof-ssa.c ICE with vector types (PR middle-end/90139, #1730454)
fix out-of-ssa with unsupported vector types (PR rtl-optimization/90756,
fix ICE with template placeholder for TTP (PR c++/86098, #1730454)

backport workaround for broken C/C++ wrappers to LAPACK (#1711346)

additional fix for the libgomp testsuite (#1707568)

backport the -fuse-ld=lld option (#1670535)
TLS model fix (#1678555, PR c++/85400)
two small autoFDO fixes (#1686082)
libgomp update (#1707568)
member template redeclaration fix (#1652704, PR c++/86747)
turn libgcc_s.so into a linker script on i?86, x86_64, ppc64le and also on
bit multilib (#1708309)
avoid using unaligned vsx or lxvd2x/stxvd2x for memcpy/memmove inline