If an expression yields 0 and is then divided-by/modulus-by then the parsing aborts. Add a debug error message to better enable debugging when this happens. Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx> --- tools/perf/util/expr.y | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y index 54260094b947..21e82a1e11a2 100644 --- a/tools/perf/util/expr.y +++ b/tools/perf/util/expr.y @@ -103,8 +103,18 @@ expr: NUMBER | expr '+' expr { $$ = $1 + $3; } | expr '-' expr { $$ = $1 - $3; } | expr '*' expr { $$ = $1 * $3; } - | expr '/' expr { if ($3 == 0) YYABORT; $$ = $1 / $3; } - | expr '%' expr { if ((long)$3 == 0) YYABORT; $$ = (long)$1 % (long)$3; } + | expr '/' expr { if ($3 == 0) { + pr_debug("division by zero\n"); + YYABORT; + } + $$ = $1 / $3; + } + | expr '%' expr { if ((long)$3 == 0) { + pr_debug("division by zero\n"); + YYABORT; + } + $$ = (long)$1 % (long)$3; + } | '-' expr %prec NEG { $$ = -$2; } | '(' if_expr ')' { $$ = $2; } | MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; } -- 2.26.2.526.g744177e7f7-goog