Regressions on native/master at commit r15-2981 vs commit r15-2975 on Linux/x86_64

[Haochen Jiang via Gcc-regression]

Regressions on master at commit r15-2981 vs commit r15-2975 on Linux/x86_64
New failures:

New passes:
FAIL: gfortran.dg/sizeof_6.f90   -O1  execution test