another attempt

Author: mrodrig6

toolchain/cmake/regular/FindFFTW.cmake

@@ -1,12 +1,11 @@
-# FindFFTW.cmake — Enhanced to support apt installs, env hints, and pkg-config
+# Robust FFTW finder: supports pkg-config, system installs, and manual hints
 
-# Try pkg-config first (if available)
 find_package(PkgConfig QUIET)
 if(PkgConfig_FOUND)
   pkg_check_modules(PC_FFTW QUIET fftw3)
 endif()
 
-# Build include + lib search paths
+# Search locations
 set(FFTW_HINTED_INCLUDE
   $ENV{FFTW_INCLUDE_DIR}
   ${PC_FFTW_INCLUDE_DIRS}
@@ -23,7 +22,7 @@ set(FFTW_HINTED_LIBRARY
   /usr/lib/x86_64-linux-gnu
 )
 
-# Locate fftw3.h and libfftw3.so
+# Locate paths
 find_path(FFTW_INCLUDE_DIR
   NAMES fftw3.h
   HINTS ${FFTW_HINTED_INCLUDE}
@@ -34,9 +33,10 @@ find_library(FFTW_LIBRARY
   HINTS ${FFTW_HINTED_LIBRARY}
 )
 
-# Required FFTW_FOUND logic
+# Safe version check
 include(FindPackageHandleStandardArgs)
-if(PC_FFTW_VERSION)
+
+if(DEFINED PC_FFTW_VERSION AND NOT "${PC_FFTW_VERSION}" STREQUAL "")
   find_package_handle_standard_args(FFTW
     REQUIRED_VARS FFTW_LIBRARY FFTW_INCLUDE_DIR
     VERSION_VAR PC_FFTW_VERSION
@@ -46,11 +46,10 @@ else()
     REQUIRED_VARS FFTW_LIBRARY FFTW_INCLUDE_DIR
   )
 endif()
-)
 
 mark_as_advanced(FFTW_INCLUDE_DIR FFTW_LIBRARY)
 
-# Define an imported target (optional but modern)
+# Optional modern target
 if(FFTW_FOUND AND NOT TARGET FFTW::FFTW)
   add_library(FFTW::FFTW UNKNOWN IMPORTED)
   set_target_properties(FFTW::FFTW PROPERTIES