Ping. On Thu, 16 Nov 2017, Nicolas Pitre wrote: > Since commit 31847b67bec0 ("kconfig: allow use of relations other than > (in)equality") it is possible to use relational operators in Kconfig > statements. However, those operators give unexpected results when > applied to bool/tristate values: > > (n < y) = y (correct) > (m < y) = y (correct) > (n < m) = n (wrong) > > This happens because relational operators process bool and tristate > symbols as strings and m sorts before n. It makes little sense to do a > lexicographical compare on bool and tristate values though. > > Documentation/kbuild/kconfig-language.txt states that expression can have > a value of 'n', 'm' or 'y' (or 0, 1, 2 respectively for calculations). > Let's make it so for relational comparisons with bool/tristate > expressions as well and document them. If at least one symbol is an > actual string then the lexicographical compare works just as before. > > Signed-off-by: Nicolas Pitre <nico@xxxxxxxxxx> > > diff --git a/Documentation/kbuild/kconfig-language.txt b/Documentation/kbuild/kconfig-language.txt > index 262722d886..c4a293a03c 100644 > --- a/Documentation/kbuild/kconfig-language.txt > +++ b/Documentation/kbuild/kconfig-language.txt > @@ -200,10 +200,14 @@ module state. Dependency expressions have the following syntax: > <expr> ::= <symbol> (1) > <symbol> '=' <symbol> (2) > <symbol> '!=' <symbol> (3) > - '(' <expr> ')' (4) > - '!' <expr> (5) > - <expr> '&&' <expr> (6) > - <expr> '||' <expr> (7) > + <symbol1> '<' <symbol2> (4) > + <symbol1> '>' <symbol2> (4) > + <symbol1> '<=' <symbol2> (4) > + <symbol1> '>=' <symbol2> (4) > + '(' <expr> ')' (5) > + '!' <expr> (6) > + <expr> '&&' <expr> (7) > + <expr> '||' <expr> (8) > > Expressions are listed in decreasing order of precedence. > > @@ -214,10 +218,13 @@ Expressions are listed in decreasing order of precedence. > otherwise 'n'. > (3) If the values of both symbols are equal, it returns 'n', > otherwise 'y'. > -(4) Returns the value of the expression. Used to override precedence. > -(5) Returns the result of (2-/expr/). > -(6) Returns the result of min(/expr/, /expr/). > -(7) Returns the result of max(/expr/, /expr/). > +(4) If value of <symbol1> is respectively lower, greater, lower-or-equal, > + or greater-or-equal than value of <symbol2>, it returns 'y', > + otherwise 'n'. > +(5) Returns the value of the expression. Used to override precedence. > +(6) Returns the result of (2-/expr/). > +(7) Returns the result of min(/expr/, /expr/). > +(8) Returns the result of max(/expr/, /expr/). > > An expression can have a value of 'n', 'm' or 'y' (or 0, 1, 2 > respectively for calculations). A menu entry becomes visible when its > diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c > index cbf4996dd9..8cee597d33 100644 > --- a/scripts/kconfig/expr.c > +++ b/scripts/kconfig/expr.c > @@ -893,7 +893,10 @@ static enum string_value_kind expr_parse_string(const char *str, > switch (type) { > case S_BOOLEAN: > case S_TRISTATE: > - return k_string; > + val->s = !strcmp(str, "n") ? 0 : > + !strcmp(str, "m") ? 1 : > + !strcmp(str, "y") ? 2 : -1; > + return k_signed; > case S_INT: > val->s = strtoll(str, &tail, 10); > kind = k_signed; > -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html