Testcase attached.  Reproduce with "opt spaces-dont-match.ll -polly-scops -polly-process-unprofitable".

Error output:
[source]/llvm/tools/polly/lib/External/isl/isl_map.c:7179: spaces don't match
#0 0x0000000002a7315c llvm::sys::PrintStackTrace(llvm::raw_ostream&) [source]/llvm/lib/Support/Unix/Signals.inc:402:11
#1 0x0000000002a736b9 PrintStackTraceSignalHandler(void*) [source]/llvm/lib/Support/Unix/Signals.inc:466:1
#2 0x0000000002a705c7 llvm::sys::RunSignalHandlers() [source]/llvm/lib/Support/Signals.cpp:45:5
#3 0x0000000002a73a40 SignalHandler(int) [source]/llvm/lib/Support/Unix/Signals.inc:256:1
#4 0x00007f1bd9de4330 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x10330)
#5 0x00007f1bd87d5c37 gsignal /build/eglibc-oGUzwX/eglibc-2.19/signal/../nptl/sysdeps/unix/sysv/linux/raise.c:56:0
#6 0x00007f1bd87d9028 abort /build/eglibc-oGUzwX/eglibc-2.19/stdlib/abort.c:91:0
#7 0x0000000003776de5 isl_handle_error [source]/llvm/tools/polly/lib/External/isl/isl_ctx.c:107:1
#8 0x00000000037a5e7a map_union_disjoint [source]/llvm/tools/polly/lib/External/isl/isl_map.c:7178:3
#9 0x00000000037a616b map_union_aligned [source]/llvm/tools/polly/lib/External/isl/isl_map.c:7277:7
#10 0x0000000003797ac4 isl_map_align_params_map_map_and [source]/llvm/tools/polly/lib/External/isl/isl_map.c:1212:3
#11 0x00000000037a5c84 isl_map_union [source]/llvm/tools/polly/lib/External/isl/isl_map.c:7295:2
#12 0x00000000037a622d isl_set_union [source]/llvm/tools/polly/lib/External/isl/isl_map.c:7308:2
#13 0x0000000002eac8f2 polly::Scop::addAssumption(polly::AssumptionKind, isl_set*, llvm::DebugLoc, polly::AssumptionSign) [source]/llvm/tools/polly/lib/Analysis/ScopInfo.cpp:3755:20
#14 0x0000000002eaa6ea polly::Scop::addRecordedAssumptions() [source]/llvm/tools/polly/lib/Analysis/ScopInfo.cpp:3770:7
#15 0x0000000002ea95dc polly::Scop::init(llvm::AAResults&, llvm::AssumptionCache&, llvm::DominatorTree&, llvm::LoopInfo&) [source]/llvm/tools/polly/lib/Analysis/ScopInfo.cpp:3154:3
#16 0x0000000002ee718d polly::ScopBuilder::buildScop(llvm::Region&, llvm::AssumptionCache&) [source]/llvm/tools/polly/lib/Analysis/ScopBuilder.cpp:667:1
#17 0x0000000002ee745b polly::ScopBuilder::ScopBuilder(llvm::Region*, llvm::AssumptionCache&, llvm::AAResults&, llvm::DataLayout const&, llvm::DominatorTree&, llvm::LoopInfo&, polly::ScopDetection&, llvm::ScalarEvolution&) [source]/llvm/tools/polly/lib/Analysis/ScopBuilder.cpp:681:3
#18 0x0000000002eb1927 polly::ScopInfoRegionPass::runOnRegion(llvm::Region*, llvm::RGPassManager&) [source]/llvm/tools/polly/lib/Analysis/ScopInfo.cpp:4342:15
#19 0x0000000001b22441 llvm::RGPassManager::runOnFunction(llvm::Function&) [source]/llvm/lib/Analysis/RegionPass.cpp:97:20
#20 0x000000000226e4bf llvm::FPPassManager::runOnFunction(llvm::Function&) [source]/llvm/lib/IR/LegacyPassManager.cpp:1509:23
#21 0x000000000226e7d5 llvm::FPPassManager::runOnModule(llvm::Module&) [source]/llvm/lib/IR/LegacyPassManager.cpp:1530:16
#22 0x000000000226f3f3 (anonymous namespace)::MPPassManager::runOnModule(llvm::Module&) [source]/llvm/lib/IR/LegacyPassManager.cpp:1586:23
#23 0x000000000226ea96 llvm::legacy::PassManagerImpl::run(llvm::Module&) [source]/llvm/lib/IR/LegacyPassManager.cpp:1689:16
#24 0x000000000226fef1 llvm::legacy::PassManager::run(llvm::Module&) [source]/llvm/lib/IR/LegacyPassManager.cpp:1720:3
#25 0x00000000008bbfb6 main [source]/llvm/tools/opt/opt.cpp:723:3
#26 0x00007f1bd87c0f45 __libc_start_main /build/eglibc-oGUzwX/eglibc-2.19/csu/libc-start.c:321:0
#27 0x00000000008928d4 _start (/usr2/efriedma/local/upstream-build-debug/bin/opt+0x8928d4)
Stack dump:
0.      Program arguments: [build]/bin/opt [test]/spaces-dont-match.ll -polly-scops -polly-process-unprofitable
1.      Running pass 'Function Pass Manager' on module '[test]/spaces-dont-match.ll'.
2.      Running pass 'Region Pass Manager' on function '@HEVC_CreateBlkPos'
3.      Running pass 'Polly - Create polyhedral description of Scops' on basic block '%for.cond85.preheader'
Aborted