I am trying to compile gcc-4.5.0 which requires ppl (among other things) . I already installed gmp, mpfr, mpc . But ./configure on ppl gives me the following error : checking for the GMP library version 4.1.3 or above... no configure: error: Cannot find GMP version 4.1.3 or higher. GMP is the GNU Multi-Precision library: Although gmp 5.x is installed and the LD_LIBRARY_PATH is set. Possible problem statements in config.log are : configure:4096: checking whether we are actually using the Intel C compiler configure:4123: gcc -c conftest.c >&5 conftest.c:11: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'me' configure:4642: checking whether we are actually using the Intel C++ compiler configure:4669: g++ -c conftest.cpp >&5 conftest.cpp:11: error: 'choke' does not name a type configure:4676: $? = 1 configure:5055: g++ -E conftest.cpp conftest.cpp:9:28: error: ac_nonexistent.h: No such file or directory configure:5124: g++ -E conftest.cpp configure:5131: $? = 0 configure:5162: g++ -E conftest.cpp conftest.cpp:9:28: error: ac_nonexistent.h: No such file or directory