Merge "Add GCC only flags to clang .mk files."

  -fgcse-after-reload \

  -frerun-cse-after-loop \

  -frename-registers \

  -fno-align-jumps \

  -fno-builtin-sin \

  -fno-caller-saves \

  -fno-early-inlining \

  -fno-move-loop-invariants \

  -fno-partial-inlining \

  -fno-strict-volatile-bitfields \

  -fno-align-jumps \

  -fno-tree-copy-prop \

  -fno-tree-loop-optimize \

  -Wa,--noexecstack

define subst-clang-incompatible-arm-flags