[Buildroot] buildroot does not copy the C++ headers to sysroot

[Peter Korsgaard]

>>>>> "bart" == bart thoelen <bart.thoelen at telenet.be> writes:

Hi,

Please keep the mailing list in CC so others can help.

 > Hi,
> when searching in the staging directory, none of the C++ headers
> (string, vector ... ) showup.

That is because those headers are part of the toolchain, so they are not
actually present in usr/include.

E.G.:

cat defconfig
BR2_arm=y
BR2_cortex_a9=y
BR2_TOOLCHAIN_EXTERNAL=y
BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201305=y

find output/host -name string
output/host/opt/ext-toolchain/arm-none-linux-gnueabi/include/c++/4.7.3/string
output/host/opt/ext-toolchain/arm-none-linux-gnueabi/include/c++/4.7.3/debug/string

And it gets correctly found by the cross compiler:

cat test.cpp
#include <iostream>
#include <string>

int main(void)
{
  std::string s("hello world");
  std::cout << s << std::endl;
  return 0;
}

strace -e open -f ./output/host/usr/bin/arm-none-linux-gnueabi-g++ -o test test.cpp 2>&1 | grep string
[pid 17378] open("/home/peko/source/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.7.3/../../../../arm-none-linux-gnueabi/include/c++/4.7.3/bits/stringfwd.h", O_RDONLY|O_NOCTTY|O_LARGEFILE) = 3
[pid 17378] open("/home/peko/source/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.7.3/../../../../arm-none-linux-gnueabi/include/c++/4.7.3/string", O_RDONLY|O_NOCTTY|O_LARGEFILE) = 3
[pid 17378] open("/home/peko/source/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.7.3/../../../../arm-none-linux-gnueabi/include/c++/4.7.3/bits/basic_string.h", O_RDONLY|O_NOCTTY|O_LARGEFILE) = 3
[pid 17378] open("/home/peko/source/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.7.3/../../../../arm-none-linux-gnueabi/include/c++/4.7.3/bits/basic_string.tcc", O_RDONLY|O_NOCTTY|O_LARGEFI


 > Below is the output of the build process during the nm_libraries.

 > I guess due to the absence of the C++ header files, the configure "assumes" they are on /usr/include.

 > A snap out of the build process...

 > checking string usability... no
 > checking string presence... no
 > checking for string... no
 > checking vector usability... no
 > checking vector presence... no
 > checking for vector... no

And what does config.log show regarding these tests?

 >>>> nm_libraries 1.0 Building
 > PATH="/home/bartt/dx2/buildroot-2014.08/output/host/bin:/home/bartt/dx2/buildroot-2014.08/output/host/sbin:/home/bartt/dx2/buildroot-2014.08/output/host/usr/bin:/home/bartt/dx2/buildroot-2014.08/output/host/usr/sbin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/opt/uClinux_10r1-4/bfin-uclinux/bin:/opt/uClinux_10r1-4/bfin-elf/bin/:/opt/freescale-coldfire-4.2/bin/:/opt/Xilinx/SDK/2013.4/gnu/arm/lin/bin:/opt/Xilinx/SDK/2013.4/bin/lin"
 > /usr/bin/make -j3 -C
 > /home/bartt/dx2/buildroot-2014.08/output/build/nm_libraries-1.0/
 > make[1]: Entering directory `/home/bartt/dx2/buildroot-2014.08/output/build/nm_libraries-1.0'
 > Making all in nmcriticalsection
 > make[2]: Entering directory
 > `/home/bartt/dx2/buildroot-2014.08/output/build/nm_libraries-1.0/nmcriticalsection'
 > /bin/bash ../libtool --tag=CXX --mode=compile
 > /home/bartt/dx2/buildroot-2014.08/output/host/usr/bin/arm-xilinx-linux-gnueabi-g++
 > -DPACKAGE_NAME=\"amfwcommonlibs\" -DPACKAGE_TARNAME=\"amfwcommonlibs\"
 > -DPACKAGE_VERSION=\"1.0\" -DPACKAGE_STRING=\"amfwcommonlibs\ 1.0\"
 > -DPACKAGE_BUGREPORT=\"\" -DPACKAGE_URL=\"\"
 > -DPACKAGE=\"amfwcommonlibs\" -DVERSION=\"1.0\" -DSTDC_HEADERS=1
 > -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1
 > -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1
 > -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1
 > -DHAVE_STDLIB_H=1 -DHAVE_STDIO_H=1 -DHAVE_DLFCN_H=1
 > -DLT_OBJDIR=\".libs/\" -I.  -I/usr/include -Wall -O3 -Werror

-I/usr/include is wrong for cross compilation, so that's why it fails
below. config.log will most likely contain hints about why the configure
test failed.

-- 
Bye, Peter Korsgaard