(gdb) start
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Temporary breakpoint 1 at 0x402538: file dvipng.c, line 37.
Starting program: /tmp/dvipng-test/dvipng -T tight -D 150 -bg Transparent -fg Blue -O 0cm,0cm foo.png foo.dvi
warning: no loadable sections found in added symbol-file system-supplied DSO at 0x7ffff7ffa000

Temporary breakpoint 1, main (argc=13, argv=0x7fffffffded8) at dvipng.c:37
37      {
(gdb) next
55        kpse_set_program_name(argv[0],"dvips");
(gdb) 
79        kpse_set_program_enabled (kpse_pk_format, makeTexPK, kpse_src_compile);
(gdb) 
82        initcolor();
(gdb) 
83        parsestdin = DecodeArgs(argc, argv);
(gdb) step
DecodeArgs (argc=13, argv=0x7fffffffded8) at misc.c:46
46        bool ppused=false;         /* Flag when -pp is used          */
(gdb) next
48        char *dviname=NULL;        /* Name of dvi file               */
(gdb) 
49        char *outname=NULL;        /* Name of output file            */
(gdb) 
51        if (argv[0]) {
(gdb) 
53          programname=strrchr(argv[0],'/');
(gdb) 
54          if (programname!=NULL)
(gdb) 
55            programname++;
(gdb) 
58          if (strncmp(programname,"dvigif",6)==0)
(gdb) 
61          programname=argv[0];
(gdb) 
62          Message(BE_NONQUIET,"This is %s",programname);
(gdb) 
63          if (strcmp(basename(programname),PACKAGE_NAME)!=0)
(gdb) 
65          Message(BE_NONQUIET," %s Copyright 2002-2010 Jan-Ake Larsson\n",
(gdb) 
This is /tmp/dvipng-test/dvipng 1.14 Copyright 2002-2010 Jan-Ake Larsson
69        for (i=1; i<argc; i++) {
(gdb) 
70          if (*argv[i]=='-') {
(gdb) 
71            char *p=argv[i]+2 ;
(gdb) 
72            char c=argv[i][1] ;
(gdb) 
73            if (c=='-') {
(gdb) 
77            switch (c) {
(gdb) 
181             if (*p == 0 && argv[i+1])
(gdb) 
182               p = argv[++i];
(gdb) 
183             if (strcmp(p,"bbox")==0) {
(gdb) 
187             } else if (strcmp(p,"tight")==0) {
(gdb) 
188               x_width_def=-1;
(gdb) 
189               y_width_def=-1;
(gdb) 
190               Message(PARSE_STDIN,"Pagesize: (tight bbox)\n");
(gdb) 
69        for (i=1; i<argc; i++) {
(gdb) 
70          if (*argv[i]=='-') {
(gdb) 
71            char *p=argv[i]+2 ;
(gdb) 
72            char c=argv[i][1] ;
(gdb) 
73            if (c=='-') {
(gdb) 
77            switch (c) {
(gdb) 
537             if (*p == 0 && argv[i+1])
(gdb) 
538               p = argv[++i] ;
(gdb) 
539             number = atoi(p);
(gdb) 
540             if (number < 10 || number > 10000)
(gdb) 
543               dpi=number;
(gdb) 
544               Message(PARSE_STDIN,"Dpi: %d\n",dpi);
(gdb) 
546             break;
(gdb) 
69        for (i=1; i<argc; i++) {
(gdb) 
70          if (*argv[i]=='-') {
(gdb) 
71            char *p=argv[i]+2 ;
(gdb) 
72            char c=argv[i][1] ;
(gdb) 
73            if (c=='-') {
(gdb) 
77            switch (c) {
(gdb) 
251             if ( *p == 'g' ) { /* -bg background color */
(gdb) 
252               p++;
(gdb) 
253               if (*p == 0 && argv[i+1])
(gdb) 
254                 p = argv[++i] ;
(gdb) 
255               if (strncmp(p,"Transparent",11) == 0 ) 
(gdb) 
256                 option_flags |= BG_TRANSPARENT_ALPHA;
(gdb) 
261               if (option_flags & BG_TRANSPARENT) 
(gdb) 
265                 Message(PARSE_STDIN,"Background: rgb %d,%d,%d\n",
(gdb) 
267               break;
(gdb) 
69        for (i=1; i<argc; i++) {
(gdb) 
70          if (*argv[i]=='-') {
(gdb) 
71            char *p=argv[i]+2 ;
(gdb) 
72            char c=argv[i][1] ;
(gdb) 
73            if (c=='-') {
(gdb) 
77            switch (c) {
(gdb) 
305             if ( *p == 'g' ) { /* -fg foreground color */
(gdb) 
306               p++;
(gdb) 
307               if (*p == 0 && argv[i+1])
(gdb) 
308                 p = argv[++i] ;
(gdb) 
309               resetcolorstack(p);
(gdb) step
resetcolorstack (p=0x7fffffffe294 "Blue") at color.c:398
398       if ( csp > 1 )
(gdb) next
400       csp=0;
(gdb) 
401       pushcolor(p) ;
(gdb) step
pushcolor (p=0x7fffffffe294 "Blue") at color.c:383
383       if ( ++csp == STACK_SIZE )
(gdb) next
385       stringrgb(p, &cstack[csp].red, &cstack[csp].green, &cstack[csp].blue);
(gdb) step
stringrgb (color=0x7fffffffe294 "Blue", r=0x41fe2c <cstack+12>, g=0x41fe30 <cstack+16>, b=0x41fe34 <cstack+20>) at color.c:259
259       DEBUG_PRINT(DEBUG_COLOR,("\n  COLOR SPEC:\t'%s' (",color));
(gdb) next
261       if (strcmp(color,"Black")==0) {
(gdb) 
263       } else if (strcmp(color,"White")==0) {
(gdb) 
265       } else if (strncmp(color,"gray ",5)==0) {
(gdb) 
268       } else if (strncmp(color,"rgb ",4)==0) {
(gdb) 
273        } else if (strncmp(color,"Gray ",5)==0) {
(gdb) 
276       } else if (strncmp(color,"RGB ",4)==0) {
(gdb) 
281       } else if (strncmp(color,"HTML ",5)==0) {
(gdb) 
288       } else if (strncmp(color,"cmy ",4)==0
(gdb) 
289                  || strncmp(color,"cmyk ",5)==0) {
(gdb) 
303       } else if (strncmp(color,"hsb ",4)==0 
(gdb) 
304                  || strncmp(color,"HSB ",4)==0) {
(gdb) 
345         if (xcp==NULL && xcpname!=NULL)
(gdb) 
347         tmp=xcp;
(gdb) print tmp
$7 = (struct colorname *) 0x5402430
(gdb) next
348         while(tmp!=NULL && strcmp(color,tmp->name)!=0)
(gdb) print tmp
$8 = (struct colorname *) 0x0
(gdb) next
350         if (tmp==NULL) {
(gdb) print tmp
$9 = (struct colorname *) 0x0
(gdb) next
351           if (colornamep==NULL)
(gdb) print colornamep
$10 = (struct colorname *) 0x0
(gdb) next
352             colornamep=LoadColornameFile(colordef[0]);
(gdb) 
353           tmp=colornamep;
(gdb) print tmp
$11 = (struct colorname *) 0x0
(gdb) next
354           while((tmp->next!=NULL || colordef[unloaded]!=NULL)
(gdb) print tmp
$13 = (struct colorname *) 0x0
(gdb) next

Program received signal SIGSEGV, Segmentation fault.
0x0000000000404604 in stringrgb (color=0x7fffffffe294 "Blue", r=0x41fe2c <cstack+12>, g=0x41fe30 <cstack+16>, b=0x41fe34 <cstack+20>) at color.c:354
354           while((tmp->next!=NULL || colordef[unloaded]!=NULL)