templight++ -E segfaults

[cout]

I noticed this when I accidentally ran templight under ccache.

pbrannan@telx-sb-dev2:~/tmp $ /home/pbrannan/bin/templight++-3.7 -c -E test.cpp
0  templight++-3.7 0x00000000010cd7c8
1  templight++-3.7 0x00000000010ccbf9
2  libpthread.so.0 0x00007fe7dec6a340
3  templight++-3.7 0x0000000001ac3b8c
4  templight++-3.7 0x0000000001167556
5  templight++-3.7 0x0000000001188fbf
6  templight++-3.7 0x0000000001168e80
7  templight++-3.7 0x0000000000548bad
8  templight++-3.7 0x00000000005106cd
9  libc.so.6       0x00007fe7dde7dec5 __libc_start_main + 245
10 templight++-3.7 0x0000000000547e24
Stack dump:
0.  Program arguments: /home/pbrannan/bin/templight++-3.7 -c -E test.cpp 
[1]    32025 segmentation fault (core dumped)  /home/pbrannan/bin/templight++-3.7 -c -E test.cpp

Backtrace from gdb:

(gdb) bt
#0  dyn_cast<clang::SemaConsumer, clang::ASTConsumer> (Val=0x0) at /home/pbrannan/download/llvm-3.7.0.src/include/llvm/Support/Casting.h:298
#1  clang::Sema::~Sema (this=0x4fdb820, __in_chrg=<optimized out>) at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/lib/Sema/Sema.cpp:259
#2  0x0000000001167556 in operator() (this=<optimized out>, __ptr=0x4fdb820) at /usr/include/c++/4.8/bits/unique_ptr.h:67
#3  reset (__p=0x4fdb820, this=<optimized out>) at /usr/include/c++/4.8/bits/unique_ptr.h:262
#4  clang::CompilerInstance::setSema (this=<optimized out>, S=<optimized out>) at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/lib/Frontend/CompilerInstance.cpp:102
#5  0x0000000001188fbf in clang::FrontendAction::EndSourceFile (this=this@entry=0x4f93a30) at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/lib/Frontend/FrontendAction.cpp:475
#6  0x0000000001168e80 in clang::CompilerInstance::ExecuteAction (this=this@entry=0x4f8fb10, Act=...)
at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/lib/Frontend/CompilerInstance.cpp:821
#7  0x0000000000548bad in ExecuteTemplightInvocation (Clang=Clang@entry=0x4f8fb10) at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/tools/templight/templight_driver.cpp:400
#8  0x00000000005106cd in ExecuteTemplightCommand (FailingCommands=..., Argv0=<optimized out>, J=..., C=..., Diags=..., TheDriver=...)
at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/tools/templight/templight_driver.cpp:463
#9  main (argc_=<optimized out>, argv_=<optimized out>) at /home/pbrannan/download/llvm-3.7.0.src/tools/clang/tools/templight/templight_driver.cpp:660

[cout]

Oops, incorrect formatting accidentally referenced issues 1-9. Fixed in an edit.

[mikael-s-persson]

Well, obviously, running templight with the "-E" option makes no sense at all. This is not something I had expected people would do, there are probably more loop-holes like that. The front-end of templight is something that I wrote in a bit of a quick-and-dirty way that manually instantiates the compiler, so I would imagine that passing in any option that would normally result in the compiler not running at all (like the "-E" option) would interact badly with templight.

Ideally, templight should terminate with an error message instead of crashing on a seg-fault. I would need to find a relatively pain-free way to catch those errors without having to exclude specific options.