[CMake] Cross compiling & conflicting declarations

[Sepp Wolf]

Hello,

I'm using CMake 3.2.2 on Solaris 10 x86. I've built a toolchain to
cross compile for SPARC, which is working fine for software with GNU
autotools.
But now I'm trying to compile Synergy, which is based on CMake, and I
have lots of troubles with double declarations:

[sepp at synergy /home/sepp/synergy]% gmake
[  0%] Building CXX object src/lib/arch/CMakeFiles/arch.dir/Arch.cpp.o
In file included from /opt/cc_sparc/sysroot/usr/include/stdlib.h:17:0,
                 from /home/sepp/synergy/src/lib/arch/../common/common.h:146,
                 from /home/sepp/synergy/src/lib/arch/../arch/Arch.h:38,
                 from /home/sepp/synergy/src/lib/arch/Arch.cpp:19:
/opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:118:38: error:
conflicting declaration of 'void* std::bsearch(const void*, const
void*, std::size_t, std::size_t, int (*)(const void*, const void*))'
with 'C++' linkage
   int (*)(const void *, const void *));
                                      ^
/opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:113:14: note:
previous declaration with 'C' linkage
 extern void *bsearch(const void *, const void *, size_t, size_t,
              ^
In file included from /opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:30:0,
                 from /opt/cc_sparc/sysroot/usr/include/stdlib.h:17,
                 from /home/sepp/synergy/src/lib/arch/../common/common.h:146,
                 from /home/sepp/synergy/src/lib/arch/../arch/Arch.h:38,
                 from /home/sepp/synergy/src/lib/arch/Arch.cpp:19:
/opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:131:61: error:
conflicting declaration 'const char* restrict'
 extern size_t mbstowcs(wchar_t *_RESTRICT_KYWD, const char *_RESTRICT_KYWD,
                                                             ^
/opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:131:33: note:
previous declaration as 'wchar_t* restrict'
 extern size_t mbstowcs(wchar_t *_RESTRICT_KYWD, const char *_RESTRICT_KYWD,
                                 ^
/opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:133:56: error:
conflicting declaration 'const char* restrict'
 extern int mbtowc(wchar_t *_RESTRICT_KYWD, const char *_RESTRICT_KYWD, size_t);
                                                        ^
/opt/cc_sparc/sysroot/usr/include/iso/stdlib_iso.h:133:28: note:
previous declaration as 'wchar_t* restrict'
 extern int mbtowc(wchar_t *_RESTRICT_KYWD, const char *_RESTRICT_KYWD, size_t);
[snip]

My CMake Toolchain-file looks like this:

# this one is important
SET(CMAKE_SYSTEM_NAME SunOS)
#this one not so much
SET(CMAKE_SYSTEM_VERSION 1)

# specify the cross compiler
SET(CMAKE_C_COMPILER   /opt/cc_sparc/bin/sparc-sun-solaris2.10-gcc)
SET(CMAKE_CXX_COMPILER /opt/cc_sparc/bin/sparc-sun-solaris2.10-g++)

SET(CMAKE_C_FLAGS   "--sysroot=/opt/cc_sparc/sysroot")
SET(CMAKE_CXX_FLAGS "--sysroot=/opt/cc_sparc/sysroot")

SET(CURL_LIBRARY /opt/cc_sparc/sysroot/lib)
SET(CURL_INCLUDE_DIR /opt/cc_sparc/sysroot/include)

SET(CMAKE_SYSROOT_PATH /opt/cc_sparc/sysroot)

# where is the target environment
SET(CMAKE_FIND_ROOT_PATH  "${CMAKE_SYSROOT_PATH}/usr/lib")

# Don't search for programs in the host environment
SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)

# Search for the libraries and headers in the target environment
SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

include_directories(SYSTEM /home/sepp/synergy/src/lib/common)
include_directories(SYSTEM /opt/cc_sparc/sysroot/usr/include)
include_directories(SYSTEM /opt/cc_sparc/sysroot/usr/include/c++/3.4.3)
include_directories(SYSTEM
/opt/cc_sparc/sysroot/usr/include/c++/3.4.3/sparc-sun-solaris2.10)

---

When I compile the same code for Solaris 10 x86 without this toolchain
and alternate sysroot, everything works fine.
Can someone tell me what I'm doing wrong?

Thanks