Hello Mark, thanks a lot for the quick response, I am not entirely sure if I already got this right, after configuring with -I/crosscompilearea/gsl-2.7.1/include in c flags I will still get the errors in make -> those are not include but rather missing src file errors, e.g. undefined reference to `gsl_rng_get’ and many others like this. So including the path might let the compiler know where it can find headers but the src code for some things still seems missing.
though, I went to the gsl_rng header file and the definition of the function seems to be in the .h file anyways. my configure command is now ./configure CC=/usr/local/gcc/bin/arm-none-eabi-gcc CXX=/usr/local/gcc/bin/arm-none-eabi-gcc LD=/usr/local/gcc/bin/arm-none-eabi-gcc AR=/usr/local/gcc/bin/arm-none-eabi-ar OBJCOPY=/usr/local/gcc/bin/arm-none-eabi-objcopy CFLAGS="-I/crosscompilearea/gsl-2.7.1/gsl -mthumb -march=armv7e-m -mfpu=fpv4-sp-d16 -mfloat-abi=soft" CXXFLAGS="-mthumb -march=armv7e-m -mfpu=fpv4-sp-d16 -mfloat-abi=soft" LDFLAGS="-I/crosscompilearea/gsl-2.7.1/gsl --specs=nano.specs --specs=nosys.specs -mthumb -march=armv7e-m -mfpu=fpv4-sp-d16 -mfloat-abi=soft" C_INCLUDE_PATH=“/crosscompilearea/gsl-2.7.1/gsl" --target=arm-none-eabi --host=arm-none-eabi I also always make clean/distclean after every attempt so that nothing else can go wrong. If you need a more detailed description of my approach please get back to me. Best Julius > On 18.09.2023, at 16:33, Mark Galassi <m...@galassi.org> wrote: > > > Dear Julius, > > Your problem seems like it might have a straightforward solution. Whenever > you do a lot of setting of CC and CXX and LD you might also want to set > C_INCLUDE_PATH and CPLUS_INCLUDE_PATH (and maybe when you get to linking also > LIBRARY_PATH). > > I would try finding the full path to the gsl_minmax.h file. Let's say it's > in /mycrosscompilearea/stuff/include/gsl/gsl_minmax.h. Then, noting that > what's being #included is gsl/gsl_minmax.h, and I would say something like > C_INCLUDE_PATH=/mycrosscompilearea/stuff/include:$C_INCLUDE_PATH > > And the same for LDFLAGS and (if you use C++) for CPLUS_INCLUDE_PATH. > > You might also be able to put a -I option into the CFLAGS setting you are > already using. > > And I would also investigate using pkg-config -- I have not used it in > cross-compiling, so it might not work for you, but you can set your > PKG_CONFIG_PATH to include /mycrosscompilearea/stuff/lib/wherever_gsl.pc_is > and then use the usual: > > pkg-config gsl --cflags > pkg-config gsl --libs > > Feel free to contact me further if you want to look at this together.
