c++ - gcc 6.1. installation, gmp/mpfr/mpc not built? -

i've installed gcc 6.1, libraries mentioned in title (gmp/mpfr/mpc) followed gnu website said:

gnu multiple precision library (gmp) version 4.3.2 (or later) necessary build gcc. if gmp source distribution found in subdirectory of gcc sources named gmp, built gcc. alternatively, if gmp installed not in library search path, have configure --with-gmp configure option. see --with-gmp-lib , --with-gmp-include. in-tree build supported gmp version download_prerequisites installs.

similar others libraries, namely downloaded sources of last version copied in gcc directory, before doing "configure", "make" , "make install" of gcc under assumption have been built gcc. when try run compiled project use gmp library say:

error while loading shared libraries: libgmp.so.10: cannot open shared object file: no such file or directory 

so looking shared object is, can't find gcc has installed it.

was supposed firstly compile gmp/mpfr , mpc before installing gcc? because thought wasn't necessary. if didn't need compile libraries gmp/mpfr , mpc supposed installed?

some further details:

i don't think did weird , complicated guess. 1. downloaded gcc , placed source in directory. 2. downloaded these libraries, tar files; 3. created 3 folders in gcc sources root (gmp, mpfr , mpc) amd expanded tars of previous step in such folders. 4. gcc executed ./configure --prefix=/path/to/gcc_build 5. executed make 6. make install

if don't use libraries can compile , execute without having problems, when need libraries returns error mentioned, after successful compiling. if in lib/ , lib64/ paths there isn't related gmp libraries.

correct me if i'm wrong.

i compile gcc 6.3.0 source website using cygwin, after research followed post here first compile gcc infrastructures including gmp, mpfr, mpc libelf, ppl (optional). try compile gcc using command (because targeted gcc linux target i686-pc-linux-gnu). compile gcc infrastructure , adding prefix to

--prefix=/opt/cross 

for gmp,mpfr,mpc libelf , ppl.

so when compile gcc, can using.

--with-gmp=/opt/cross --with-mpfr=/opt/cross --with-mpc=/opt/cross 

and gcc automatically followed infrastructure needed on /opt/cross directory.

because many times try to

./contrib/download_prerequisites 

following this method,always getting error when try compile gcc.

i have done method, compiling gcc binutils i686-pc-linux-gnu. haven't try use compiling linux kernel using cygwin.

sorry english, , sorry if answers oot.