yylineno sometimes incorrect if noinput option set

[JC3]

flex 2.6.4 (via winflexbison)

if %option yylineno noinput is set, then yylineno sometimes reports incorrect values (sequentially increasing but offset by a random number). for any given full run of the scanner it is randomly correct or incorrect, depending on planetary alignment.

i believe it is because, afaict, when noinput is set there does not seem to be any code path that initializes yy_buffer_state::yy_bs_lineno to 0 during buffer setup. but i'm not sure because it was hard looking through unfamiliar code.

if it matters: i'm using yy_scan_string to set up the buffer and my full option set is:

%option noinput nounput noyywrap yylineno never-interactive batch warn
%option bison-bridge bison-locations reentrant
%option case-insensitive

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workaround option 1: don't set noinput

workaround option 2: manually initialze yy_bs_lineno after creating a buffer e.g.:

YY_BUFFER_STATE yy = yy_scan_string(...);
yy->yy_bs_lineno = 0; /* or maybe it should be 1, i dunno. */

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note: other yy_buffer_state members should probably be assessed for similar issues, yy_bs_column in particular.