MantisBT - CMake
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IDProjectCategoryView StatusDate SubmittedLast Update
0013128CMakeModulespublic2012-04-13 15:342016-06-10 14:31
Reporterdevurandom 
Assigned ToKitware Robot 
PrioritynormalSeveritymajorReproducibilityalways
StatusclosedResolutionmoved 
PlatformOSOS Version
Product VersionCMake 2.8.7 
Target VersionFixed in Version 
Summary0013128: find_package_handle_standard_args in CONFIG_MODE requires ${NAME}_CONFIG even if ${NAME}_FOUND
DescriptionConsider following code, which will always bail out with an error:
find_package(Eigen3 QUIET)
message(E3F: ${EIGEN3_FOUND})
find_package(Eigen3 QUIET NO_MODULE PATHS "${MY_CONFIG_PATH}")
message(E3F: ${EIGEN3_FOUND})
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Eigen3 CONFIG_MODE)

Both E3F messages print TRUE, but FPHSA still aborts with a failure.

I assume this is because of following code:
  IF(FPHSA_CONFIG_MODE)
    LIST(INSERT FPHSA_REQUIRED_VARS 0 ${_NAME}_CONFIG)
and:
  FOREACH(_CURRENT_VAR ${FPHSA_REQUIRED_VARS})
    IF(NOT ${_CURRENT_VAR})
      SET(${_NAME_UPPER}_FOUND FALSE)
Steps To Reproduce
Additional InformationWhat I am trying to achieve is the following:
Eigen3 should be searched in the system, if it is not found my project comes with a local copy of it (via ${MY_CONFIG_PATH}/Eigen3Config.cmake). No matter where it was found, I would like only one message to be output about the presence or absence of Eigen3. If possible they should look similar, but just point to different paths.

I previously had following code:
find_package(Eigen3)
if (NOT EIGEN3_FOUND)
  set(EIGEN3_INCLUDE_DIR "${CMAKE_SOURCE_DIR}")
  find_package(Eigen3 REQUIRED)
But that outputs one irritating "Could NOT find ..." message even if Eigen3 is found locally. Further the success message, if Eigen3 was found locally, is missing.
TagsNo tags attached.
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Issue History
Date ModifiedUsernameFieldChange
2012-04-13 15:34devurandomNew Issue
2012-04-13 15:47devurandomNote Added: 0029149
2012-04-13 16:14David ColeNote Added: 0029150
2012-04-16 09:16Brad KingNote Added: 0029171
2012-04-16 15:46Alex NeundorfAssigned To => Alex Neundorf
2012-04-16 15:46Alex NeundorfStatusnew => assigned
2012-04-16 15:49Alex NeundorfNote Added: 0029185
2012-04-16 17:40devurandomNote Added: 0029195
2012-04-18 15:10Alex NeundorfNote Added: 0029223
2012-04-18 15:15Brad KingNote Added: 0029224
2012-04-18 15:15Brad KingAssigned ToAlex Neundorf =>
2012-04-18 15:15Brad KingStatusassigned => backlog
2016-06-10 14:28Kitware RobotNote Added: 0042024
2016-06-10 14:28Kitware RobotStatusbacklog => resolved
2016-06-10 14:28Kitware RobotResolutionopen => moved
2016-06-10 14:28Kitware RobotAssigned To => Kitware Robot
2016-06-10 14:31Kitware RobotStatusresolved => closed

Notes
(0029149)
devurandom   
2012-04-13 15:47   
"they should look similar":
"they" refers to the messages for the cases where Eigen3 was found locally or in the system.
(0029150)
David Cole   
2012-04-13 16:14   
Why not simply append or prepend your own path to CMAKE_MODULE_PATH before calling find_package?

If you append, your config file will be found last, if you prepend, your config file will be found first. In the case where you'd prefer the system Eigen, you should append and then call find_package only once with REQUIRED.

Wouldn't that be simpler?
(0029171)
Brad King   
2012-04-16 09:16   
The documentation of find_package_handle_standard_args states "Use the option CONFIG_MODE if your FindXXX.cmake module is a wrapper". The entire macro is meant only for use inside a Find module.

The FindEigen3 module itself should do the config-mode search. Look at FindHDF5 and FindVTK for examples that try config mode and fall back to old-style search.
(0029185)
Alex Neundorf   
2012-04-16 15:49   
I agree with Brad.
Also, the documentation for find_package() says:
"The full path to the configuration file is stored in the cmake variable <package>_CONFIG."

So when you use fphsa(Foo ... CONFIG_MODE ), it does the right thing and checks for Foo_CONFIG.

I think there is nothing to change here.
(0029195)
devurandom   
2012-04-16 17:40   
Re: David: Appending a directory containing *Config.cmake files to CMAKE_MODULE_PATH, when that path also contains Find*.cmake files, does not do what I'd expect: It sees the Find* file and just uses that, instead of falling back to *Config. So it appears preferring this or that library does not work in the way you described.

Re: Brad and Alex: Why should every single package implement that fallback mechanism? Wouldn't it be easier if CMake implemented it and it could be used automatically, if desired?
Could you add a mode/version of fphsa or find_package, that either uses the fallback mechanism I hinted at above, or just summarises the previous find_package(QUIET) calls?
(0029223)
Alex Neundorf   
2012-04-18 15:10   
If you post a patch we'll have a look at it.
(0029224)
Brad King   
2012-04-18 15:15   
FWIW I'm not interested in any more automatic fallback behavior in find_package. If the command sees a Find module in CMAKE_MODULE_PATH it will enter Module mode and never consider Config mode.

Any functionality along these lines belongs in FPHSA (or a new macro/function) to help Find modules do Config mode first and then fall back to normal testing. It is up to the package-specific Find modules to know whether newer versions of the package provide package config files.
(0042024)
Kitware Robot   
2016-06-10 14:28   
Resolving issue as `moved`.

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