-Wchar-subscript warnings

[sanjayankur31]

While building iv for NeuroFedora, we saw a few -Wchar-subscript warnings:

make[2]: Leaving directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
make[2]: Entering directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
libtool: compile:  g++ -DHAVE_CONFIG_H -I. -I. -I../include -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -c InterViews/fbrowser.cpp  -fPIC -DPIC -o InterViews/.libs/fbrowser.o
InterViews/fbrowser.cpp: In constructor 'ivFileBrowser::ivFileBrowser(ivWidgetKit*, ivAction*, ivAction*)':
InterViews/fbrowser.cpp:145:13: warning: array subscript has type 'char' [-Wchar-subscripts]
  145 |  fb.key_[k->key] = k->func;
      |          ~~~^~~
InterViews/fbrowser.cpp: In member function 'virtual void ivFileBrowser::keystroke(const ivEvent&)':
InterViews/fbrowser.cpp:256:33: warning: array subscript has type 'char' [-Wchar-subscripts]
  256 |  FileBrowserKeyFunc f = fb.key_[c];
      |                                 ^
make[2]: Leaving directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
make[2]: Entering directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
--
make[2]: Leaving directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
make[2]: Entering directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
gcc -DHAVE_CONFIG_H -I. -I. -I../include   -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -DCOLORIMETRY_SUPPORT -DJPEG_SUPPORT -DYCBCR_SUPPORT -DCMYK_SUPPORT -DHAVE_IEEEFP=1 -DUSE_VARARGS=0 -DUSE_PROTOTYPES=1 -DUSE_CONST=1 -I../include/TIFF TIFF/mkg3states.c -o TIFF/mkg3states
TIFF/mkg3states.c: In function 'find_horiz_mode_prefix':
TIFF/mkg3states.c:492:41: warning: array subscript has type 'char' [-Wchar-subscripts]
  492 |      (int) horiz_mode_prefix_count, "WB"[color], prefix);
      |                                         ^
At top level:
TIFF/mkg3states.c:5:13: warning: 'rcsid' defined but not used [-Wunused-variable]
--
make[2]: Leaving directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
make[2]: Entering directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
libtool: compile:  g++ -DHAVE_CONFIG_H -I. -I. -I../include -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -c Unidraw/catalog.cpp  -fPIC -DPIC -o Unidraw/.libs/catalog.o
Unidraw/catalog.cpp: In function 'void HexDecode(const char*, ivColorIntensity&, ivColorIntensity&, ivColorIntensity&)':
Unidraw/catalog.cpp:138:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  138 |     r  = hexintmap[enc[0]] << 4;
      |                    ~~~~~^
Unidraw/catalog.cpp:139:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  139 |     r |= hexintmap[enc[1]];
      |                    ~~~~~^
Unidraw/catalog.cpp:140:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  140 |     g  = hexintmap[enc[2]] << 4;
      |                    ~~~~~^
Unidraw/catalog.cpp:141:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  141 |     g |= hexintmap[enc[3]];
      |                    ~~~~~^
Unidraw/catalog.cpp:142:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  142 |     b  = hexintmap[enc[4]] << 4;
      |                    ~~~~~^
Unidraw/catalog.cpp:143:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  143 |     b |= hexintmap[enc[5]];
      |                    ~~~~~^
Unidraw/catalog.cpp: In function 'void HexGrayDecode(const char*, ivColorIntensity&)':
Unidraw/catalog.cpp:168:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  168 |     g  = hexintmap[enc[0]] << 4;
      |                    ~~~~~^
Unidraw/catalog.cpp:169:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  169 |     g |= hexintmap[enc[1]];
      |                    ~~~~~^
Unidraw/catalog.cpp: In member function 'void ivCatalog::ReadBitmapData(ivBitmap*, std::istream&)':
Unidraw/catalog.cpp:1699:42: warning: array subscript has type 'char' [-Wchar-subscripts]
 1699 |             unsigned int val = hexintmap[hexchar];
      |                                          ^~~~~~~
make[2]: Leaving directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'
make[2]: Entering directory '/builddir/build/BUILD/iv-74f120781bc2def0cc4d1f9f547c07037e8a7a74/src/lib'

Since char maybe signed on some machines, this may result in undefined behaviour, so worth looking into too.

[sanjayankur31]

build-log.txt