Force build to be dependent on changes in header files in QtCreator/QMake

dusktreader

It seems that by default the build functionality of QtCreator is only dependent on changes in the source files. So, for example, if I change a file in the SOURCES variable, initiating a "run" or "build" request from QtCreator will rebuild all objects dependent on those source files. However, if I change a file in the HEADERS list and initiate a "build" or "run" request, no objects will be rebuilt.

How do I make the current build of my application dependent on a header file so that if a header changes the dependent objects are rebuilt?

I know how to do this with standard make (i.e. add dependency to a .h file). How can I specify this sort of thing in a QMake .pro file?

Franzk

Haven't tested, but maybe adding paths to DEPENDPATH could help. For example:

@DEPENDPATH += . src include@

? This user is from outside of this forum

by default it will rebuild when you modify any header.. can you post your .pro file here

kalle

QMake will only observe dependencies in files listed in .pro files, or files in DEPENDPATH and INCLUDEPATH.

dusktreader

Here is my .pro file:

@
TARGET = outlierdetecttest
TEMPLATE = app

INCLUDEPATH +=
../../../tools
../..

SOURCES +=
main.cpp
../../../tools/tools.cpp

HEADERS +=
../../../tools/tools.h
../../outlier.h
@

This project simply tests the functionality of a custom header. The header has templated source code, so there is no accompanying .cpp file. The layout of the projects is as follows

~/analysis/ # This is the main source folder for my large project
|- outlier.h
|- other source and header files
~/analysis/sandbox/outlierdetecttest/ # This is the folder where the project for testing the outlier detection header lies
|- main.cpp
|- outlierdetecttest.pro

The tools.h files are only used for debugging, and really aren't necessary.--

Now, suppose I have already built the project. I run it and decide to change something in the header. After I edit the header and hit the build button (or ctrl-b ), nothing happens. If, however, I edit the main.cpp source file and request a rebuild, then the executable is rebuilt.

I do not want to make the main source folder ( ~/analysis) part of the dependency path. I only want to make the outlierdetecttest build depend on changes in the header file. How can I do this?

julrich

I just encountered this issue with Qt 4.8 and I guess there is a bug in QMake.
In my project, the .pro file contained the following:

@
DEPENDPATH += .
INCLUDEPATH += .
./include
@

(of course, the header files are added to HEADERS)

This lead to a makefile where the only dependency of the object file was the source file (e.g. "myfile.o: myfile.cpp"). However, the dependencies of the moc source files were fine.
As soon as I change the .pro file like this:
@
DEPNENDPATH += .
./include
INCLUDEPATH += .
./include
@

all dependencies are generated correctly. And now the dependencies even contain the ui generated header files which are not in the ./include directory!
So I guess that the dependency generation does not take place when the DEPENDPATH only contains "." or is completely empty.