Regressions on master at commit r16-1508 vs commit r16-1506 on Linux/x86_64

[Haochen Jiang]

Regressions on master at commit r16-1508 vs commit r16-1506 on Linux/x86_64
New failures:

New passes:
FAIL: g++.dg/coroutines/torture/exceptions-test-01-n4849-a.C   -O2  execution test
FAIL: g++.dg/coroutines/torture/exceptions-test-01-n4849-a.C   -O2  execution test
FAIL: g++.dg/coroutines/torture/exceptions-test-01-n4849-a.C   -O2 -flto -fno-use-linker-plugin -flto-partition=none  execution test
FAIL: g++.dg/coroutines/torture/exceptions-test-01-n4849-a.C   -O2 -flto -fno-use-linker-plugin -flto-partition=none  execution test
FAIL: g++.dg/coroutines/torture/exceptions-test-01-n4849-a.C   -O3 -g  execution test
FAIL: g++.dg/coroutines/torture/exceptions-test-01-n4849-a.C   -O3 -g  execution test