Host arch is amd64 multilib. USE="static-analyzer system-cxx-headers -debug -multitarget -test" =sys-devel/clang-3.0-r2 Simple example: $ cat a.cc #include <iostream> int main() { return 0; } $ clang++ -c a.cc # works fine $ clang++ -m32 -c a.cc > In file included from a.cc:1: > /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/iostream:38:10: fatal error: 'bits/c++config.h' file > not found > #include <bits/c++config.h> > ^ > 1 error generated. Fails. running with -v reveals the problem: $ clang++ -v -m32 -c a.cc clang version 3.0 (tags/RELEASE_30/final) Target: i386-pc-linux-gnu Thread model: posix "/usr/bin/clang" -cc1 -triple i386-pc-linux-gnu -emit-obj -mrelax-all -disable-free -disable-llvm-verifier -main-file-name a.cc -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -target-cpu pentium4 -target-linker-version 2.22 -momit-leaf-frame-pointer -v -coverage-file a.o -resource-dir /usr/bin/../lib/clang/3.0 -fmodule-cache-path /var/tmp/clang-module-cache -internal-isystem /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4 -internal-isystem /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/x86_64-pc-linux-gnu32 -internal-isystem /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/backward -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib/clang/3.0/include -internal-externc-isystem /usr/include -internal-externc-isystem /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include -fdeprecated-macro -ferror-limit 19 -fmessage-length 115 -fgnu-runtime -fobjc-runtime-has-arc -fobjc-runtime-has-weak -fobjc-fragile-abi -fcxx-exceptions -fexceptions -fdiagnostics-show-option -fcolor-diagnostics -o a.o -x c++ a.cc clang -cc1 version 3.0 based upon llvm 3.0 hosted on x86_64-pc-linux-gnu ignoring nonexistent directory "/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/x86_64-pc-linux-gnu32" ignoring nonexistent directory "/usr/local/include" #include "..." search starts here: #include <...> search starts here: /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4 /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/backward /usr/bin/../lib/clang/3.0/include /usr/include /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include End of search list. In file included from a.cc:1: /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/iostream:38:10: fatal error: 'bits/c++config.h' file not found #include <bits/c++config.h> ^ 1 error generated. The interesting bit is: > ignoring nonexistent directory "/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/include/g++-v4/x86_64-pc-linux-gnu32" It misses '/' separator in the end: x86_64-pc-linux-gnu32 -> x86_64-pc-linux-gnu/32 I currently workaround it by adding proper '-I' explicitely.
From bug #402365 the path setup will be better/easier in 3.1 (I hope). In the meantime I have added the missing "/" in the configure step, that has to be one of the bumps with least changes I ever made! Fixed with clang-3.0-r3
