Linux file stripped, but still holds information it shouldn't

I have a program which I stripped of all symbols, and confirmed as follows:

file /usr/local/mypapp
/usr/local/myapp: ELF 64-bit LSB executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=0f9f3c44a5bbbaefb0a64306e981323f5655e873, for GNU/Linux 3.2.0, stripped

My program contains a runtime error (Qt signal name is wrong), and at runtime the following error is written to the system log:

QObject::connect: No such signal RunProcessAsync::sig_write(ELevelWarning, Types::ESources, quint64, QString) in /mnt/myserver/data/development/myapp/src/external-sharedfiles/systemcommands/testfile.cpp:60

So it would appear the full name of the source file, the function call, and the class name are all still in the executable! How / why? The file is supposed to be stripped?

As Alan said above, strip doesn't change debug messages. What strip does is remove debugging symbols from the binary - these are data used by debuggers such as gdb and are stored in special sections of a binary. Debug messages on the other hand are things like qDebug() and some of these are generated automatically for you by Qt's connect() function. Using the build flag QT_NO_DEBUG_OUTPUT will disable these messages.

You should also consider using the newer syntax for connect that uses templates to validate your connect statements at compile time. This will make it easier to prevent errors such as the one that message is flagging.