Switch all C++ usages of ABS, MIN, and MAX macros to std::{abs,min,max}

[Kurt Schwehr]

In the vain of (almost) always preferring functions to macros, GDAL should use the std:: version for C++ code.

Examples of converting: r31275, r31273 + r31274

There are still C usages:

find . -name \*.c | xargs egrep -l '[^a-zA-Z_](MIN|MAX|ABS)[^a-zA-Z_]' | egrep -v 'lib(csf|jpeg|png|geotiff)|giflib|degrib18'
./ogr/ogrsf_frmts/dgn/dgndump.c
./ogr/ogrsf_frmts/avc/avc_bin.c
./ogr/ogrsf_frmts/avc/avc_binwr.c
./ogr/ogrsf_frmts/avc/avc_rawbin.c
./ogr/ogrsf_frmts/avc/avc_e00gen.c
./ogr/ogrsf_frmts/avc/avc_e00parse.c
./ogr/ogrsf_frmts/shape/shpopen.c
./ogr/osr_cs_wkt.c
./frmts/nitf/nitffile.c
./frmts/nitf/nitfimage.c
./frmts/gxf/gxfopen.c
./frmts/dted/dted_ptstream.c
./frmts/dted/dted_api.c
./frmts/dted/dted_create.c
./apps/gdaltindex.c

Can we convert any of these files to C++?

[Kurt Schwehr]

  rawdataset.cpp:179:21: [0;1;31merror:  call to 'abs' is ambiguous
        nLineSize = std::abs(nPixelOffset) * nBlockXSize;
                    ^~~~~~~~
 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:660:1: [0;1;30mnote: candidate function
abs(float __x) _NOEXCEPT {return fabsf(__x);}

 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:664:1: [0;1;30mnote: candidate function
abs(double __x) _NOEXCEPT {return fabs(__x);}

 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:668:1: [0;1;30mnote: candidate function
abs(long double __x) _NOEXCEPT {return fabsl(__x);}

​http://en.cppreference.com/w/cpp/numeric/math/abs says long long abs( long long n ); is C++11.

Confusion follows...

[Kurt Schwehr]

r31276 should fix the mac build. integer abs templates are in cstdlib, whereas cmath provides the floating point templates.

[Even Rouault]

avc and shapelib have "upstream" projects (although rather inactive those last years). Other files are pretty much internal to GDAL. Although if we kill all C files, I'm not sure how we're going to verify that the public headers can still be included from a pure C file, as we don't have any .c files in autotest/cpp anymore. Might be good to add at least one.

[Even Rouault]

This ticket has been automatically closed because Trac is no longer used for GDAL bug tracking, since the project has migrated to GitHub. If you believe this ticket is still valid, you may file it to ​https://github.com/OSGeo/gdal/issues if it is not already reported there.