If a vector is empty, you're not allowed to access any

elements, even if it is only to take the address.  Test:
break-anti-dependencies.ll with ENABLE_EXPENSIVE_CHECKS.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62576 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan Sands 2009-01-20 09:05:19 +00:00
parent e08eb9ca1d
commit f90fb345db

View File

@ -49,10 +49,11 @@ namespace llvm {
///
SUnit *NewSUnit(MachineInstr *MI) {
#ifndef NDEBUG
const SUnit *Addr = &SUnits[0];
const SUnit *Addr = SUnits.empty() ? 0 : &SUnits[0];
#endif
SUnits.push_back(SUnit(MI, (unsigned)SUnits.size()));
assert(Addr == &SUnits[0] && "SUnits std::vector reallocated on the fly!");
assert((Addr == 0 || Addr == &SUnits[0]) &&
"SUnits std::vector reallocated on the fly!");
SUnits.back().OrigNode = &SUnits.back();
return &SUnits.back();
}