[LLVMdev] [NVPTX] Strange assertion around BlockToChain.clear(); in Release+Asserts build

[Dmitry N. Mikushin]

Hi,

After building out project in release mode, caught an assertion, which
we have not seen before:

hello_f: /tmp/rpmbuild_debug/BUILD/llvm/build/include/llvm/ADT/DenseMap.h:126:
void llvm::DenseMap<KeyT, ValueT, KeyInfoT>::clear() [with KeyT =
llvm::MachineBasicBlock*, ValueT = <unnamed>::BlockChain*, KeyInfoT =
llvm::DenseMapInfo<llvm::MachineBasicBlock*>]: Assertion `NumEntries
== 0 && "Node count imbalance!"' failed.

Program received signal SIGABRT, Aborted.
0x00007ffff785c945 in raise () from /lib64/libc.so.6
(gdb) bt
#0  0x00007ffff785c945 in raise () from /lib64/libc.so.6
#1  0x00007ffff785df21 in abort () from /lib64/libc.so.6
#2  0x00007ffff7855810 in __assert_fail () from /lib64/libc.so.6
#3  0x00007ffff62b283d in (anonymous
namespace)::MachineBlockPlacement::runOnMachineFunction(llvm::MachineFunction&)
() from /opt/kernelgen/lib/libLLVM-3.2svn.so
#4  0x00007ffff64cfb9f in
llvm::FPPassManager::runOnFunction(llvm::Function&) () from
/opt/kernelgen/lib/libLLVM-3.2svn.so
#5  0x00007ffff64cfc43 in
llvm::FPPassManager::runOnModule(llvm::Module&) () from
/opt/kernelgen/lib/libLLVM-3.2svn.so
#6  0x00007ffff64cf6e4 in
llvm::MPPassManager::runOnModule(llvm::Module&) () from
/opt/kernelgen/lib/libLLVM-3.2svn.so
#7  0x00007ffff64cf840 in llvm::PassManagerImpl::run(llvm::Module&) ()
from /opt/kernelgen/lib/libLLVM-3.2svn.so
#8  0x00007ffff75aa57a in TrackedPassManager::run
(this=0x7fffffffc8d0, M=...) at ../bugpoint/TrackedPassManager.h:168
#9  0x00007ffff75a66bf in kernelgen::runtime::codegen (runmode=1,
kernel=0x7fffffffd420, m=0x833ab0) at codegen.cpp:454
#10 0x00007ffff75871b1 in main (argc=1, argv=0x7fffffffdcc8,
envp=0x7fffffffdcd8) at entry.cpp:318
#11 0x00007ffff7848bc6 in __libc_start_main () from /lib64/libc.so.6
#12 0x00000000004008f9 in _start () at ../sysdeps/x86_64/elf/start.S:113

Any ideas?.. What could it be related to?

Thanks,
- D.