cpl_recode_iconv.cpp compile error on freebsd 10

[springmeyer]

Hitting this error compiling GDAL latest on freebsd 10:

/bin/sh /usr/home/ec2-user/mapnik-packaging/osx/out/packages/gdal/gdal/libtool --mode=compile --tag=CXX clang++  -Wno-pragmas -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include  -DNDEBUG -O3  -D_FILE_OFFSET_BITS=64 -fPIC  -Wall  -DOGR_ENABLED -I/usr/home/ec2-user/mapnik-packaging/osx/out/packages/gdal/gdal/port -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64 -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64 -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include 	  -DHAVE_LIBZ -c -o cpl_recode_iconv.lo cpl_recode_iconv.cpp
libtool: compile:  clang++ -Wno-pragmas -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include -DNDEBUG -O3 -D_FILE_OFFSET_BITS=64 -fPIC -Wall -DOGR_ENABLED -I/usr/home/ec2-user/mapnik-packaging/osx/out/packages/gdal/gdal/port -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64 -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64 -I/usr/home/ec2-user/mapnik-packaging/osx/out/build-cpp03-libstdcpp-gcc-x86_64/include -DHAVE_LIBZ -c cpl_recode_iconv.cpp -o cpl_recode_iconv.o
warning: unknown warning option '-Wno-pragmas' [-Wunknown-warning-option]
cpl_recode_iconv.cpp:106:13: error: no matching function for call to 'iconv'
            iconv( sConv, &pszSrcBuf, &nSrcLen, &pszDstBuf, &nDstLen );
            ^~~~~
/usr/include/iconv.h:56:8: note: candidate function not viable: no known conversion from 'char **' to 'const char **' for 2nd argument
size_t  iconv(iconv_t, const char ** __restrict,
        ^
cpl_recode_iconv.cpp:256:13: error: no matching function for call to 'iconv'
            iconv( sConv, &pszSrcBuf, &nSrcLen, &pszDstBuf, &nDstLen );
            ^~~~~
/usr/include/iconv.h:56:8: note: candidate function not viable: no known conversion from 'char **' to 'const char **' for 2nd argument
size_t  iconv(iconv_t, const char ** __restrict,
        ^
1 warning and 2 errors generated.
gmake[1]: *** [cpl_recode_iconv.lo] Error 1

I'm using:

FreeBSD ip-10-233-153-7 10.0-RELEASE FreeBSD 10.0-RELEASE #0 r260789: Thu Jan 16 22:34:59 UTC 2014     root@snap.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64

I found that port/cpl_config.h looks like:

/* Define as const if the declaration of iconv() needs const. */
#define ICONV_CONST const

/* For .cpp files, define as const if the declaration of iconv() needs const. */
#define ICONV_CPP_CONST

And I can workaround the problem by changing it to:

/* Define as const if the declaration of iconv() needs const. */
#define ICONV_CONST const

/* For .cpp files, define as const if the declaration of iconv() needs const. */
#define ICONV_CPP_CONST const

[Even Rouault]

Hum, this is weird. There's a configure test for that. Could you try the following ? I suspect there must be a warning that occurs and make the test fail

    echo '#include <iconv.h>' > testiconv.cpp
    echo 'int main(int argc, char** argv) { iconv_t cd; return iconv (cd, (const char **) 0, 0, 0, 0); } ' >> testiconv.cpp
    clang++ testiconv.cpp -c

[springmeyer]

Not seeing a warning:

$ echo '#include <iconv.h>' > testiconv.cpp
$ echo 'int main(int argc, char** argv) { iconv_t cd; return iconv (cd, (const char **) 0, 0, 0, 0); } ' >> testiconv.cpp
$ clang++ testiconv.cpp -c
$ clang++ testiconv.cpp -c -pedantic
$ clang++ testiconv.cpp -c -pedantic -Wall
testiconv.cpp:2:61: warning: variable 'cd' is uninitialized when used here
      [-Wuninitialized]
int main(int argc, char** argv) { iconv_t cd; return iconv (cd, (const char ...
                                                            ^~
testiconv.cpp:2:45: note: initialize the variable 'cd' to silence this warning
int main(int argc, char** argv) { iconv_t cd; return iconv (cd, (const c...
                                            ^
                                             = NULL
1 warning generated.
$ clang++ -v
FreeBSD clang version 3.3 (tags/RELEASE_33/final 183502) 20130610
Target: x86_64-unknown-freebsd10.0
Thread model: posix

[Even Rouault]

Dane, could you test the following ? GDAL is compiled with -Wall so the warning causes the test to fail.

trunk r27276 "configure: fix for cpl_recode_iconv.cpp compilation error on freebsd 10 (#5452)"

[springmeyer]

Works! Nice fix.

[Even Rouault]

Cool. Backported to branches/1.11 in r27277