Recently I compiled gcc 4.1.1 with minGW in windows according to the instructions here. Now, when I try to compile a test file that includes float.h I get the following errors: error: '_clear87' was not declared in this scope error: '_control87' was not declared in this scope I tried to run the file the -v -H flags: E:\temp>g++ -v -H main.cpp Using built-in specs. Target: mingw32 Configured with: ../gcc-4.1.1 /configure --with-gcc --with-gnu-ld --with-gnu-as --host=mingw32 --target=mingw32 --prefix=/mingw --enable-threads --disable-nls --enable-languages=c,c++ --disable-win32-registry --disable-shared --without-x Thread model: win32 gcc version 4.1.1 c:/mingw/bin/../libexec/gcc/mingw32/4.1.1/cc1plus.exe -quiet -v -iprefix c:\mingw\bin\../lib/gcc/mingw32/4.1.1/ -H main.cpp -quiet -dumpbase main.cpp -auxbase main -version -o C:\DOCUME~1\Dave\LOCALS~1\Temp/ccqWaaaa.s ignoring nonexistent directory "/mingw/include" ignoring nonexistent directory "C:/MinGW/mingw32/include" ignoring nonexistent directory "/mingw/include" #include "..." search starts here: #include <...> search starts here: c:/mingw/bin/../lib/gcc/mingw32/4.1.1/include C:/MinGW/include/c++/4.1.1 C:/MinGW/include/c++/4.1.1/mingw32 C:/MinGW/include/c++/4.1.1/backward C:/MinGW/include C:/MinGW/lib/gcc/mingw32/4.1.1/include End of search list. What seems to happen is that gcc searches the gcc system files first and not the "C:/MinGW/include". anyone knows why? and how can I change the order of the included files? Dave