Syntax checker parser fails when compile options contains "-include"

[sezaru]

Hello there,

When opening the rtags project on emacs, irony syntax checker will fail to parse it's compile options, resulting in the error:
Error from syntax checker irony: parsing failed

Any file will get the same error, but for this example I used the file ClangIndexer.cpp, the irony server will return this compile options from it:

~/irony-server/build $ ./src/irony-server get-compile-options /home/devel/rtags/build
  /home/devel/rtags/src/ClangIndexer.cpp

execute: Command{action=Command::GetCompileOptions,
                 file='/home/devel/rtags/src/ClangIndexer.cpp',
                 dir='/home/devel/rtags/build', line=0, column=0, flags=[],
                 unsavedFiles.count=0, opt=off}
(
(("/usr/bin/c++" "-DCLANG_LIBDIR=/usr/lib/llvm-3.6/lib" "-DOS_Linux" "-DRCT_HAVE_OPENSSL"
  "-DRCT_HAVE_ZLIB" "-I/usr/lib/llvm-3.6/include" "-D_GNU_SOURCE" "-D__STDC_CONSTANT_MACROS"
  "-D__STDC_FORMAT_MACROS" "-D__STDC_LIMIT_MACROS" "-Wall" "-Wextra" "-Wpointer-arith"
  "-Wnon-virtual-dtor" "-fno-rtti" "-std=c++11" "-Wall" "-Wextra" "-Wpointer-arith"
  "-Wnon-virtual-dtor" "-fno-rtti" "-std=c++11" "-Wstrict-aliasing=2" "-fno-exceptions"
  "-Wcast-qual" "-fPIC" "-fstack-protector-all" "-Wstack-protector" "-O3" "-DNDEBUG"
  "-I/home/devel/rtags/src" "-I/home/devel/rtags/src/rct"
  "-I/home/devel/rtags/build/src/include" "-Winvalid-pch" "-include"
  "/home/devel/rtags/build/src/cotire/rtags_CXX_prefix.hxx" "-o"
  "CMakeFiles/rtags.dir/ClangIndexer.cpp.o" "-c" "/home/devel/rtags/src/ClangIndexer.cpp" )
  . "/home/devel/rtags/build/src")
)

;;EOT

The problem that makes the error occurs is this option:

"-include" "/home/devel/rtags/build/src/cotire/rtags_CXX_prefix.hxx"

If I remove it from my compile options the parser works just fine.

[Sarcasm]

Just to be sure, does the file actually exist?
It seems to be a build generated file, as such it may not exist until before the first build.

Are you able to reproduce it with a minimal example?

[sezaru]

The file exists in the build directory.

I didn't created a small example since it was occurring in the rtags source code, but I will try to create one and post here

[sezaru]

The small project is in this link as promissed, when running cmake + make, the files will be created inside cotire directory, and irony will start to fail to parse it

https://www.dropbox.com/s/duko3u3gn75z9ed/test_irony.tar.bz2?dl=0

[Sarcasm]

Ok, it seems the issue is not with -include but more about precompiled headers.

I can get irony-mode to work if I generate the compile_commands.json for Clang:

env CC=clang CXX=clang++ cmake -G Ninja -DCMAKE_EXPORT_COMPILE_COMMANDS=ON

But the compile commands for gcc don't work:

cmake -G Ninja -DCMAKE_EXPORT_COMPILE_COMMANDS=ON ../

And I think it makes sense. The precompiled headers are often a compiler-specific internal representation of the code. So even if Clang is mostly compatible with GCC, it does not support GCC precompiled headers.

I used the following command to know that:

clang++ -fsyntax-only -Qunused-arguments -I../minimal_example -I../include -Winvalid-pch -include /home/papin_g/Downloads/test_irony_gcc/build/cotire/minimal_example_CXX_prefix.hxx ~/Downloads/test_irony_gcc/src/main.cpp
error: input is not a PCH file:
      '/home/papin_g/Downloads/test_irony_gcc/build/cotire/minimal_example_CXX_prefix.hxx.gch'
fatal error: '/home/papin_g/Downloads/test_irony_gcc/build/cotire/minimal_example_CXX_prefix.hxx.gch' does not appear
      to be a precompiled header file
2 errors generated.

[sezaru]

Thanks, that really fix it, will close the issue since the origin of it is outside irony.