>>> Emerging (1 of 1) sys-fs/mdadm-3.1.5::gentoo
 * mdadm-3.1.5.tar.bz2 BLAKE2B SHA512 size ;-) ...                                                                         
[ ok ]
>>> Unpacking source...
>>> Unpacking mdadm-3.1.5.tar.bz2 to 
/var/tmp/portage/sys-fs/mdadm-3.1.5/work
 * Applying mdadm-3.0-dont-make-man.patch ...                                                                              
[ ok ]
 * Applying mdadm-2.6-syslog-updates.patch ...                                                                             
[ ok ]
 * Applying mdadm-2.6.4-mdassemble.patch ...                                                                               
[ ok ]
 * Applying mdadm-3.1.5-cflags.patch ...                                                                                   
[ ok ]
>>> Source unpacked in /var/tmp/portage/sys-fs/mdadm-3.1.5/work
>>> Compiling source in 
/var/tmp/portage/sys-fs/mdadm-3.1.5/work/mdadm-3.1.5 ...
make -j4 CC=x86_64-pc-linux-gnu-gcc CWFLAGS=-Wall 'CXFLAGS=-O2 -pipe 
-march=amdfam10 -mcx16 -msahf -mpopcnt --param l1-cache-size=64 --param 
l1-cache-line-size=64 --param l2-cache-size=1024 -mtune=amdfam10' all 
mdassemble 
x86_64-pc-linux-gnu-gcc -Wall -O2 -pipe -march=amdfam10 -mcx16 -msahf 
-mpopcnt --param l1-cache-size=64 --param l1-cache-line-size=64 --param 
l2-cache-size=1024 -mtune=amdfam10 -DSendmail=\""/usr/sbin/sendmail 
-t"\" -DCONFFILE=\"/etc/mdadm.conf\" 
-DCONFFILE2=\"/etc/mdadm/mdadm.conf\" -DMAP_DIR=\"/dev/.mdadm\" 
-DMAP_FILE=\"map\" -DMDMON_DIR=\"/dev/.mdadm\" -DUSE_PTHREADS   -c -o 
mdadm.o mdadm.c
x86_64-pc-linux-gnu-gcc -Wall -O2 -pipe -march=amdfam10 -mcx16 -msahf 
-mpopcnt --param l1-cache-size=64 --param l1-cache-line-size=64 --param 
l2-cache-size=1024 -mtune=amdfam10 -DSendmail=\""/usr/sbin/sendmail 
-t"\" -DCONFFILE=\"/etc/mdadm.conf\" 
-DCONFFILE2=\"/etc/mdadm/mdadm.conf\" -DMAP_DIR=\"/dev/.mdadm\" 
-DMAP_FILE=\"map\" -DMDMON_DIR=\"/dev/.mdadm\" -DUSE_PTHREADS   -c -o 
config.o config.c
x86_64-pc-linux-gnu-gcc -Wall -O2 -pipe -march=amdfam10 -mcx16 -msahf 
-mpopcnt --param l1-cache-size=64 --param l1-cache-line-size=64 --param 
l2-cache-size=1024 -mtune=amdfam10 -DSendmail=\""/usr/sbin/sendmail 
-t"\" -DCONFFILE=\"/etc/mdadm.conf\" 
-DCONFFILE2=\"/etc/mdadm/mdadm.conf\" -DMAP_DIR=\"/dev/.mdadm\" 
-DMAP_FILE=\"map\" -DMDMON_DIR=\"/dev/.mdadm\" -DUSE_PTHREADS   -c -o 
mdstat.o mdstat.c
x86_64-pc-linux-gnu-gcc -Wall -O2 -pipe -march=amdfam10 -mcx16 -msahf 
-mpopcnt --param l1-cache-size=64 --param l1-cache-line-size=64 --param 
l2-cache-size=1024 -mtune=amdfam10 -DSendmail=\""/usr/sbin/sendmail 
-t"\" -DCONFFILE=\"/etc/mdadm.conf\" 
-DCONFFILE2=\"/etc/mdadm/mdadm.conf\" -DMAP_DIR=\"/dev/.mdadm\" 
-DMAP_FILE=\"map\" -DMDMON_DIR=\"/dev/.mdadm\" -DUSE_PTHREADS   -c -o 
ReadMe.o ReadMe.c
mdadm.c: In function 'main':
mdadm.c:1047:24: warning: implicit declaration of function 'minor' 
[-Wimplicit-function-declaration]
    ident.super_minor = minor(stb.st_rdev);
                        ^
x86_64-pc-linux-gnu-gcc -Wall -O2 -pipe -march=amdfam10 -mcx16 -msahf 
-mpopcnt --param l1-cache-size=64 --param l1-cache-line-size=64 --param 
l2-cache-size=1024 -mtune=amdfam10 -DSendmail=\""/usr/sbin/sendmail 
-t"\" -DCONFFILE=\"/etc/mdadm.conf\" 
-DCONFFILE2=\"/etc/mdadm/mdadm.conf\" -DMAP_DIR=\"/dev/.mdadm\" 
-DMAP_FILE=\"map\" -DMDMON_DIR=\"/dev/.mdadm\" -DUSE_PTHREADS   -c -o 
util.o util.c
mdadm.c:104:6: warning: variable 'auto_update_home' set but not used 
[-Wunused-but-set-variable]
  int auto_update_home = 0;
      ^
util.c: In function 'md_get_version':
util.c:196:9: warning: implicit declaration of function 'major' 
[-Wimplicit-function-declaration]
     if (major(stb.st_rdev) == MD_MAJOR)
         ^
util.c: In function 'add_dev':
util.c:677:16: warning: implicit declaration of function 'minor' 
[-Wimplicit-function-declaration]
    dm->minor = minor(stb->st_rdev);
                ^
util.c: In function 'get_md_name':
util.c:914:10: warning: implicit declaration of function 'makedev' 
[-Wimplicit-function-declaration]
   rdev = makedev(mdp, (-1-dev)<<6);
          ^
util.c: In function 'open_container':
util.c:1406:8: error: called object 'major' is not a function or 
function pointer
   (int)major(st.st_rdev), (int)minor(st.st_rdev));
        ^
util.c:1400:6: note: declared here
  int major, minor;
      ^
util.c:1406:32: error: called object 'minor' is not a function or 
function pointer
   (int)major(st.st_rdev), (int)minor(st.st_rdev));
                                ^
util.c:1400:13: note: declared here
  int major, minor;
             ^
make: *** [<builtin>: util.o] Error 1