Description of problem:
Please update doxygen to 1.7.6.1 in rawhide, the current 1.7.6 is looping forever on gnuradio-3.5.0 build.

Version-Release number of selected component (if applicable):
doxygen-1.7.6

How reproducible:
Always

Steps to Reproduce:
1. Build gnuradio-3.5.0
  
Actual results:
doxygen loops forever

Expected results:
doxygen finishes

Additional info:
Strace snippet of infinite loop:
...
access("/builddir/build/BUILD/gnuradio-3.5.0/gruel/src/lib/pmt/", F_OK) = 0
lstat("/builddir/build/BUILD/gnuradio-3.5.0/gruel/src/lib/pmt/", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
access("/builddir/build/BUILD/gnuradio-3.5.0/gruel/src/lib/pmt/gr_core_api.h", F_OK) = -1 ENOENT (No such file or directory)
access("/builddir/build/BUILD/gnuradio-3.5.0/gruel/src/lib/pmt/", F_OK) = 0
lstat("/builddir/build/BUILD/gnuradio-3.5.0/gruel/src/lib/pmt/", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
access("/builddir/build/BUILD/gnuradio-3.5.0/gruel/src/lib/pmt/gr_core_api.h", F_OK) = -1 ENOENT (No such file or directory)
....

Probably fixed by (not sure):
id 665720: Included patch to fix hang issue when non-empty INCLUDE_PATH was used.