Bug 1087433

Description of problem:
make check of flex in arch ppc64le triggers a segmentation fault on test-bison-yylval and test-bison-yylloc

Version-Release number of selected component (if applicable):
flex-2.5.37-4.fc21.ppc64le
bison-3.0.2-1.fc21.ppc64le

How reproducible:
rpmbuild --target ppc64le (with make check enabled)
or make check
or ./test-bison-yylval < ./test.input

Actual results:
gcc -c -o scanner.o -I. -I../.. -I../.. -I.  -fPIC -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches  -m64 scanner.c
scanner.c:2899:16: warning: 'input' defined but not used [-Wunused-function]
     static int input  (yyscan_t yyscanner)
                ^
gcc -c -o main.o -I. -I../.. -I../.. -I.  -fPIC -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches  -m64 main.c
gcc -o test-bison-yylval -Wl,-z,relro  parser.o scanner.o main.o
./test-bison-yylval < ./test.input
/bin/sh: line 1:  6658 Segmentation fault      ./test-bison-yylval < ./test.input
make[5]: *** [test] Error 139

Results:
Tests succeeded: 44
Tests FAILED: 2

Additional info:
investigating test-bison-yylval with gdb gives:
-bash-4.3# gdb --args test-bison-yylval
GNU gdb (GDB) Fedora 7.7-4.fc21
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "ppc64le-redhat-linux-gnu".
...
Reading symbols from test-bison-yylval...done.
(gdb) run < test.input
Starting program: /home/root/rpmbuild/BUILD/flex-2.5.37/tests/test-bison-yylval/test-bison-yylval < test.input

Program received signal SIGSEGV, Segmentation fault.
testlex (yylval_param=0x3fffffffe7b0, yyscanner=0x1ffffff247b0)
    at scanner.c:2412
2412	    yylval = yylval_param;
Missing separate debuginfos, use: debuginfo-install glibc-2.18.90-12.1.2.fc21.ppc64le
(gdb) backtrace
#0  testlex (yylval_param=0x3fffffffe7b0, yyscanner=0x1ffffff247b0)
    at scanner.c:2412
#1  0x00000000100016d8 in testparse (scanner=0x10030010) at parser.c:1157
#2  0x0000000010000a0c in main (argc=<optimized out>, argv=<optimized out>)
    at main.c:33

after closer investigation on code I saw that yylval_param have been passed as parametre to yylex (or testlex) function of scaneer.c.
in generated code scanner.c, testlex is defined as follow:
extern int testlex \
               (YYSTYPE * yylval_param ,yyscan_t yyscanner);

int testlex \
               (YYSTYPE * yylval_param , yyscan_t yyscanner)
{
        register yy_state_type yy_current_state;

Unfortunatly, yylex is called from generated code parser.c with only one parameter instead of two.
yylex is called in following manner:
  /* YYCHAR is either YYEMPTY or YYEOF or a valid lookahead symbol.  */
  if (yychar == YYEMPTY)
    {
      YYDPRINTF ((stderr, "Reading a token: "));
      yychar = yylex (&yylval);
    }

I am not a specialist of bison or flex and I didn't find if a parameter could be change in parser.y or scanner.l to correct the problem but changing the generated code parser.c by adding the second parameter at the call,
yychar = yylex (&yylval, scanner);
make the test succeed.