failed with png 1.6

[kemin711]

libtool: compile: g++ -DHAVE_CONFIG_H -I. -I.. -I./../include -DLIBPLOT -DLIBPLOTTER -O2 -MT z_write.lo -MD -MP -MF .deps/z_write.Tpo -c z_write.cc -fPIC -DPIC -o .libs/z_write.o
z_write.cc: In function ‘void _our_error_fn_stream(png_struct*, const char*)’:
z_write.cc:519:19: error: invalid use of incomplete type ‘png_struct {aka struct png_struct_def}’
longjmp (png_ptr->jmpbuf, 1);
^
In file included from z_write.cc:43:0:
/usr/local/include/png.h:475:16: note: forward declaration of ‘png_struct {aka struct png_struct_def}’
typedef struct png_struct_def png_struct;

png.h is version 1.6

[kemin711]

just editing z_write.c seems not enough, another round of autoreconf, configure wipes out the change.