How to have CMake show headers-that are not part of any binary target-in the IDE?

Several months down the line, I did not find a way to directly list the header files for an INTERFACE library.

Since the question still has some views, here is what I ended up doing (i.e. what appears like the lesser hack currently available).

Imagine module A is a header only library. In the CMakeLists.txt declaring its target:

# Define 'modA_headers' variable to list all the header files
set(modA_headers 
  utility.h
  moreUtilities.h
  ...)

add_library(moduleA INTERFACE) # 'moduleA' is an INTERFACE pseudo target

#
# From here, the target 'moduleA' can be customised
#
target_include_directories(moduleA ...) # Transitively forwarded
install(TARGETS moduleA ...)

#
#  HACK: have the files showing in the IDE, under the name 'moduleA_ide'
#
add_custom_target(moduleA_ide SOURCES ${modA_headers})

I do not accept this answer, since I expect further releases of CMake to offer a more semantically correct approach, which will then be accepted : )