Performing C++ SOURCE FILE Test _OFFT_IS_64BIT failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/gmake" "cmTC_95ea7/fast"
/usr/bin/gmake -f CMakeFiles/cmTC_95ea7.dir/build.make CMakeFiles/cmTC_95ea7.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_95ea7.dir/src.cxx.o
/usr/bin/i686-pc-linux-gnu-g++ -D_GNU_SOURCE -D_LARGEFILE64_SOURCE   -DQT_NO_DEBUG -DNDEBUG -O2 -pipe -march=pentium4m -mtune=pentium4m -Wno-error=jump-misses-init -Wno-error=sign-compare -D_OFFT_IS_64BIT   -o CMakeFiles/cmTC_95ea7.dir/src.cxx.o -c /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx
/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx:7:36: warning: left shift count >= width of type [-Wshift-count-overflow]
 #define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
                                    ^
/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx:8:23: note: in expansion of macro ‘LARGE_OFF_T’
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721 && LARGE_OFF_T % 2147483647 == 1) ? 1 : -1];
                       ^~~~~~~~~~~
/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx:7:60: warning: left shift count >= width of type [-Wshift-count-overflow]
 #define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
                                                            ^
/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx:8:23: note: in expansion of macro ‘LARGE_OFF_T’
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721 && LARGE_OFF_T % 2147483647 == 1) ? 1 : -1];
                       ^~~~~~~~~~~
/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx:8:97: error: size of array ‘off_t_is_large’ is negative
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721 && LARGE_OFF_T % 2147483647 == 1) ? 1 : -1];
                                                                                                 ^
gmake[1]: *** [CMakeFiles/cmTC_95ea7.dir/build.make:66: CMakeFiles/cmTC_95ea7.dir/src.cxx.o] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
gmake: *** [Makefile:126: cmTC_95ea7/fast] Error 2

Source file was:

#include <sys/types.h>
 /* Check that off_t can represent 2**63 - 1 correctly.
    We can't simply define LARGE_OFF_T to be 9223372036854775807,
    since some C++ compilers masquerading as C compilers
    incorrectly reject 9223372036854775807.  */
#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
  int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721 && LARGE_OFF_T % 2147483647 == 1) ? 1 : -1];
  int main() { return 0; }

Determining if the pthread_create exist failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/gmake" "cmTC_57e1f/fast"
/usr/bin/gmake -f CMakeFiles/cmTC_57e1f.dir/build.make CMakeFiles/cmTC_57e1f.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_57e1f.dir/CheckSymbolExists.c.o
/usr/bin/i686-pc-linux-gnu-gcc -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE -D_LARGEFILE64_SOURCE   -DQT_NO_DEBUG -DNDEBUG -O2 -pipe -march=pentium4m -mtune=pentium4m -Wno-error=jump-misses-init -Wno-error=sign-compare -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration    -o CMakeFiles/cmTC_57e1f.dir/CheckSymbolExists.c.o -c /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/CheckSymbolExists.c
Linking C executable cmTC_57e1f
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_57e1f.dir/link.txt --verbose=1
/usr/bin/i686-pc-linux-gnu-gcc -O2 -pipe -march=pentium4m -mtune=pentium4m -Wno-error=jump-misses-init -Wno-error=sign-compare -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration   -Wl,-O1 -Wl,--as-needed  -rdynamic CMakeFiles/cmTC_57e1f.dir/CheckSymbolExists.c.o  -o cmTC_57e1f 
CMakeFiles/cmTC_57e1f.dir/CheckSymbolExists.c.o: In function `main':
CheckSymbolExists.c:(.text.startup+0xc): undefined reference to `pthread_create'
collect2: error: ld returned 1 exit status
gmake[1]: *** [CMakeFiles/cmTC_57e1f.dir/build.make:98: cmTC_57e1f] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
gmake: *** [Makefile:126: cmTC_57e1f/fast] Error 2

File /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/CheckSymbolExists.c:
/* */
#include <pthread.h>

int main(int argc, char** argv)
{
  (void)argv;
#ifndef pthread_create
  return ((int*)(&pthread_create))[argc];
#else
  (void)argc;
  return 0;
#endif
}

Determining if the function pthread_create exists in the pthreads failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/gmake" "cmTC_be0b7/fast"
/usr/bin/gmake -f CMakeFiles/cmTC_be0b7.dir/build.make CMakeFiles/cmTC_be0b7.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_be0b7.dir/CheckFunctionExists.c.o
/usr/bin/i686-pc-linux-gnu-gcc -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE -D_LARGEFILE64_SOURCE   -DQT_NO_DEBUG -DNDEBUG -O2 -pipe -march=pentium4m -mtune=pentium4m -Wno-error=jump-misses-init -Wno-error=sign-compare -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -DCHECK_FUNCTION_EXISTS=pthread_create   -o CMakeFiles/cmTC_be0b7.dir/CheckFunctionExists.c.o -c /usr/share/cmake/Modules/CheckFunctionExists.c
Linking C executable cmTC_be0b7
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_be0b7.dir/link.txt --verbose=1
/usr/bin/i686-pc-linux-gnu-gcc -O2 -pipe -march=pentium4m -mtune=pentium4m -Wno-error=jump-misses-init -Wno-error=sign-compare -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -DCHECK_FUNCTION_EXISTS=pthread_create  -Wl,-O1 -Wl,--as-needed  -rdynamic CMakeFiles/cmTC_be0b7.dir/CheckFunctionExists.c.o  -o cmTC_be0b7 -lpthreads 
/usr/lib/gcc/i686-pc-linux-gnu/7.3.0/../../../../i686-pc-linux-gnu/bin/ld: cannot find -lpthreads
collect2: error: ld returned 1 exit status
gmake[1]: *** [CMakeFiles/cmTC_be0b7.dir/build.make:98: cmTC_be0b7] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
gmake: *** [Makefile:126: cmTC_be0b7/fast] Error 2


Performing C++ SOURCE FILE Test HAVE_LQR_0_4 failed with the following output:
Change Dir: /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/gmake" "cmTC_08fea/fast"
/usr/bin/gmake -f CMakeFiles/cmTC_08fea.dir/build.make CMakeFiles/cmTC_08fea.dir/build
gmake[1]: Entering directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_08fea.dir/src.cxx.o
/usr/bin/i686-pc-linux-gnu-g++ -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE -D_LARGEFILE64_SOURCE -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include   -DQT_NO_DEBUG -DNDEBUG -O2 -pipe -march=pentium4m -mtune=pentium4m -Wno-error=jump-misses-init -Wno-error=sign-compare -std=c++0x -fno-operator-names -fno-exceptions -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wnon-virtual-dtor -Woverloaded-virtual -Werror=return-type -Wvla -Wdate-time -pedantic -Wsuggest-override -Wlogical-op -Wzero-as-null-pointer-constant -std=c++0x -fno-operator-names -fno-exceptions -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wnon-virtual-dtor -Woverloaded-virtual -Werror=return-type -Wvla -Wdate-time -pedantic -Wsuggest-override -Wlogical-op -Wzero-as-null-pointer-constant -std=c++0x -fno-operator-names -fno-exceptions -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wnon-virtual-dtor -Woverloaded-virtual -Werror=return-type -Wvla -Wdate-time -DHAVE_LQR_0_4   -o CMakeFiles/cmTC_08fea.dir/src.cxx.o -c /var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx
/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp/src.cxx:2:14: fatal error: lqr.h: No such file or directory
     #include <lqr.h>
              ^~~~~~~
compilation terminated.
gmake[1]: *** [CMakeFiles/cmTC_08fea.dir/build.make:66: CMakeFiles/cmTC_08fea.dir/src.cxx.o] Error 1
gmake[1]: Leaving directory '/var/tmp/portage/media-gfx/digikam-6.0.0/work/digikam-6.0.0_build/CMakeFiles/CMakeTmp'
gmake: *** [Makefile:126: cmTC_08fea/fast] Error 2

Source file was:

    #include <lqr.h>

    int main()
    {
    LqrImageType t = LQR_RGB_IMAGE;
    return 0;
    }