Tutorial: Improve Step 3

* Move `option(USE_MYMATH...` to the same location in all CMakeLists files
This commit is contained in:
Betsy McPhail
2019-07-09 13:36:53 -04:00
committed by Brad King
parent 49ce4d6ff4
commit bc64401c3d
5 changed files with 31 additions and 18 deletions

View File

@@ -7,15 +7,15 @@ project(Tutorial VERSION 1.0)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED True)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# does this system provide the log and exp functions?
include(CheckSymbolExists)
set(CMAKE_REQUIRED_LIBRARIES "m")
check_symbol_exists(log "math.h" HAVE_LOG)
check_symbol_exists(exp "math.h" HAVE_EXP)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# configure a header file to pass some of the CMake settings
# to the source code
configure_file(TutorialConfig.h.in TutorialConfig.h)

View File

@@ -7,15 +7,15 @@ project(Tutorial VERSION 1.0)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED True)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# does this system provide the log and exp functions?
include(CheckSymbolExists)
set(CMAKE_REQUIRED_LIBRARIES "m")
check_symbol_exists(log "math.h" HAVE_LOG)
check_symbol_exists(exp "math.h" HAVE_EXP)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# configure a header file to pass some of the CMake settings
# to the source code
configure_file(TutorialConfig.h.in TutorialConfig.h)

View File

@@ -7,15 +7,15 @@ project(Tutorial VERSION 1.0)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED True)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# does this system provide the log and exp functions?
include(CheckSymbolExists)
set(CMAKE_REQUIRED_LIBRARIES "m")
check_symbol_exists(log "math.h" HAVE_LOG)
check_symbol_exists(exp "math.h" HAVE_EXP)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# configure a header file to pass some of the CMake settings
# to the source code
configure_file(TutorialConfig.h.in TutorialConfig.h)

View File

@@ -7,15 +7,15 @@ project(Tutorial VERSION 1.0)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED True)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# does this system provide the log and exp functions?
include(CheckSymbolExists)
set(CMAKE_REQUIRED_LIBRARIES "m")
check_symbol_exists(log "math.h" HAVE_LOG)
check_symbol_exists(exp "math.h" HAVE_EXP)
# should we use our own math functions
option(USE_MYMATH "Use tutorial provided math implementation" ON)
# configure a header file to pass the version number only
configure_file(TutorialConfig.h.in TutorialConfig.h)

View File

@@ -253,12 +253,14 @@ requirements are:
- ``target_include_directories``
- ``target_link_libraries``
First up is MathFunctions. We first state that anybody linking to MathFunctions
needs to include the current source directory, while MathFunctions itself
doesn't. So this can become an ``INTERFACE`` usage requirement.
Let's refactor our code from `Adding a Library (Step 2)`_ to use the modern
CMake approach of usage requirements. We first state that anybody linking to
MathFunctions needs to include the current source directory, while
MathFunctions itself doesn't. So this can become an ``INTERFACE`` usage
requirement.
Remember ``INTERFACE`` means things that consumers require but the producer
doesn't. Update ``MathFunctions/CMakeLists.txt`` with:
doesn't. Add the following lines to the end of ``MathFunctions/CMakeLists.txt``:
.. literalinclude:: Step4/MathFunctions/CMakeLists.txt
:language: cmake
@@ -266,7 +268,18 @@ doesn't. Update ``MathFunctions/CMakeLists.txt`` with:
Now that we've specified usage requirements for MathFunctions we can safely
remove our uses of the ``EXTRA_INCLUDES`` variable from the top-level
CMakeLists.
CMakeLists, here:
.. literalinclude:: Step4/CMakeLists.txt
:language: cmake
:start-after: # add the MathFunctions library
:end-before: # add the executable
And here:
.. literalinclude:: Step4/CMakeLists.txt
:language: cmake
:start-after: # so that we will find TutorialConfig.h
Once this is done, run **cmake** or **cmake-gui** to configure the project
and then build it with your chosen build tool or by using ``cmake --build .``
@@ -355,7 +368,7 @@ CMakeLists file as follows:
.. literalinclude:: Step6/CMakeLists.txt
:language: cmake
:start-after: # does this system provide the log and exp functions?
:end-before: # should we use our own math functions
:end-before: # configure a header file to pass some of the CMake settings
Now let's add these defines to ``TutorialConfig.h.in`` so that we can use them
from ``mysqrt.cxx``: