macOS C++ XCode debugging

[kamy]

Hey guys,

I use CLang compiler to build our binaries for the MACOSX platform.
I also provide the '-g' option which ensures that debugging symbols are enabled.

This is my CLang command with the flags - Do note that the '-g' flag is provided

clang -I/ac/head/tools/mtxtests -I/ac/head/library/include -I/ac/head/library/src/VersLib -I/ac/head/library/src/XmlLib -I/ac/head/library/src/ZipLib -I/ac/head/tools/googletest/include -DAGENT_VERS_MAJ=0 -DAGENT_VERS_MIN=0 -DAGENT_VERS_REV=\"0\" -DBUILDNUMBER=\"Undefined\" -DUNIX -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS -DMACOSX -DDEBUG -DIMPORT_MTXLIBS -DUNICODE -D_UNICODE -m64 -stdlib=libstdc++ -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk -Wall -fPIC -fpermissive -g -fvisibility=hidden -E /ac/head/tools/mtxtests/library/PortLib/MtxString.cpp

I want to use XCode to debug an isssue.
I issue a sleep(30) command, my program waits 30 seconds, so that gives me time to go to XCode - Debug-->Attach To Process --> mtxtests (my executable)

As soon as XCode attaches, the sleep is aborted and teh execution continues!
Thus, I cant debug any code.
Also my XCode project has 'C++ library' as the target

What could be the problem?

If i remember i used to be able to debug fine when i used to use the LLVM-GCC compiler. But with Maverics, we need to move to CLang...

Any suggestions would be appreciated.

 

[kamy]

C++ Sample file debugging

I dug around some more info. Apparently xcode you can build executables with "dsym" debug information, which puts the debug info in a separate file (instead of embedding it in the executable)

But as we are using the command line, i dont see any DEBUG Symbol files or "dsym" files.

So i used the util to generate the Symbol files
dsymutil mtxtests -o mtxtests.dSYM

Still the same behavior. The executable sleeps and as soon as we attach the process , the process resumes without allowing me to debug!!!

 

[kamy]

Trying some more

Ok. This is me again trying more stuff...

I created a simple .C file
And compiled using CLang

clang -g -o tempraturefn tempraturefn.c

This time i see 'tempraturefn.dSYM' automatically created...

i see that the executable sleeps and then i open the file in XCode and try to attach my executable and voilla i can debug!!

So this means that something is wrong with the flags am sending, while compiling my code .....

clang -I/ac/head/tools/mtxtests -I/ac/head/library/include -I/ac/head/library/src/VersLib -I/ac/head/library/src/XmlLib -I/ac/head/library/src/ZipLib -I/ac/head/tools/googletest/include -DAGENT_VERS_MAJ=0 -DAGENT_VERS_MIN=0 -DAGENT_VERS_REV=\"0\" -DBUILDNUMBER=\"Undefined\" -DUNIX -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS -DMACOSX -DDEBUG -DIMPORT_MTXLIBS -DUNICODE -D_UNICODE -m64 -stdlib=libstdc++ -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk -Wall -fPIC -fpermissive -g -fvisibility=hidden -E /ac/head/tools/mtxtests/library/PortLib/MtxString.cpp

 

[subsonix]

But as we are using the command line, i dont see any DEBUG Symbol files or "dsym" files.

Just add the -g flag and a .dSYM file will be created with the same name as your target. So for example,

clang test.c -g

will create a.out and a.out.dSYM

So this means that something is wrong with the flags am sending, while compiling my code .....

Have you considered using a makefile?

 

[kamy]

Just add the -g flag and a .dSYM file will be created with the same name as your target. So for example,

clang test.c -g

will create a.out and a.out.dSYM



Have you considered using a makefile?

Hey subsonix,

if you see the flags for our compilation command, we do pass the "-g" flag.
Yes we do use a Makefile.

But when i use our compilation command, it does not generate any 'dSYM' file.

Is a 'dSYM' file mandatory for debugging?
If yes, that explains the fact that my sample file could be dubbuged, but not my main executable.

 

[subsonix]

Hey subsonix,

if you see the flags for our compilation command, we do pass the "-g" flag.
Yes we do use a Makefile.

But when i use our compilation command, it does not generate any 'dSYM' file.

Is a 'dSYM' file mandatory for debugging?
If yes, that explains the fact that my sample file could be dubbuged, but not my main executable.

As far as I know it gives you more information when you debug with debug symbols, but you should be able to attach a debugger anyway. However, it should create a dSYM file, perhaps it has something to do with the fact that you are building a library.