在./configure是出现
checking for XpmReadFileToXpmImage in -lXpm... no
configure: Disabling support for xpm
checking whether to support tiff... auto
checking for LIBTIFF... no
checking for TIFFClientOpen in -ltiff... no
configure: Disabling support for tiff
checking whether to support webp... auto
checking for WebPGetInfo in -lwebp... no
configure: Disabling support for webp
checking for simple visibility declarations... yes
checking whether we are building for a Win32 host... no
checking CFLAGS for maximum warnings... -Wall
** Configuration summary for libgd 2.2.3:
Support for Zlib: yes
Support for PNG library: yes
Support for JPEG library: yes
Support for WebP library: no
Support for TIFF library: no
Support for Freetype 2.x library: yes
Support for Fontconfig library: no
Support for Xpm library: no
Support for liq library: no
Support for pthreads: yes
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating src/Makefile
config.status: creating tests/Makefile
config.status: creating tests/test_config.h
config.status: creating config/Makefile
config.status: creating config/gdlib-config
config.status: creating config/gdlib.pc
config.status: creating src/config.h
config.status: executing depfiles commands
config.status: executing libtool commands
make时报错
libtool: compile: gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I/usr/local/zlib/include -I/usr/local/libpng/include -I/usr/local/libpng/include/libpng16 -I/usr/local/freetype/include -I/usr/local/freetype/include/freetype2 -I/usr/local/jpeg8/include -Werror -g -O2 -fvisibility=hidden -Wall -MT gdft.lo -MD -MP -MF .deps/gdft.Tpo -c gdft.c -fPIC -DPIC -o .libs/gdft.o
gdft.c:143:15: error: 'font_pattern' defined but not used [-Werror=unused-function]
static char * font_pattern(char **fontpath, char fontpattern)
^
gdft.c:449:12: error: 'useFontConfig' defined but not used [-Werror=unused-function]
static int useFontConfig(int flag)
^
cc1: all warnings being treated as errors
make[2]: ** [gdft.lo] Error 1
make[2]: Leaving directory /root/libgd-2.2.3/src'/root/libgd-2.2.3/src'
make[1]: *** [all] Error 2
make[1]: Leaving directory
make: *** [all-recursive] Error 1
请问这是什么问题？如何解决呢？
修改下编译器的警告级别，这些不是错误。
gcc的编译级别比较高，对于警告也认为是错误的。代码中有几个变量没有使用
我是这么做的（全部注释掉）：
142 #ifndef HAVE_LIBFONTCONFIG
143 //static char * font_pattern(char **fontpath, char fontpattern)
144 //{
145 // (void)fontpath;
146 // (void)fontpattern;
147 //
148 // return "libgd was not built with FontConfig support\n";
149 //}
150 #endif / HAVE_LIBFONTCONFIG */
449 //static int useFontConfig(int flag)
450 //{
451 //#ifdef HAVE_LIBFONTCONFIG
452 // if (fontConfigFlag) {
453 // return (!(flag & gdFTEX_FONTPATHNAME));
454 // }
455 //#endif
456 // return flag & gdFTEX_FONTCONFIG;
457 //}
但是再编译$ sudo make，又出现了新的错误：
collect2: ld returned 1 exit status
make[2]: *** [libgd.la] Error 1
make[2]: Leaving directory /home/tomcat/lamp/libgd-2.2.3/src'/home/tomcat/lamp/libgd-2.2.3/src'
make[1]: *** [all] Error 2
make[1]: Leaving directory