shithub: mc

Info  •  Files  •  Log  •  Branches

Add hook into frontend for sizeof() folding.

	Before, code like:

		const f = {
			var buf: byte[sizeof(int)]
		}

	would crash us, because `sizeof` would not get folded.

	A slightly subtle point: muse doens't install a hook here,
	but since it's already handling processed usefiles, the
	array sizes should already be prefolded for its viewing
	pleasure.

--- a/6/main.c

+++ b/6/main.c

@@ -202,6 +202,7 @@

 	optinit(&ctx, "cd:?hSo:I:9G:O:", argv, argc);

 	asmsyntax = Defaultasm;

+	sizefn = size;

 	while (!optdone(&ctx)) {

 		switch (optnext(&ctx)) {

 		case 'O':

--- a/parse/fold.c

+++ b/parse/fold.c

@@ -13,6 +13,8 @@

 #include "util.h"

 #include "parse.h"

+size_t (*sizefn)(Node *n);

+

 static int

 getintlit(Node *n, vlong *v)

 {

@@ -249,6 +251,10 @@

 		break;

 	case Ocast:

 		r = foldcast(n);

+		break;

+	case Osize:

+		if (sizefn)

+			r = val(n->loc, sizefn(n->expr.args[0]), exprtype(n));

 		break;

 	default:

 		break;

--- a/parse/infer.c

+++ b/parse/infer.c

@@ -2031,6 +2031,9 @@

 		t->fixed = 1;

 		if (t->type == Tyarray) {

 			typesub(t->asize, noerr);

+			t->asize = fold(t->asize, 1);

+			if (exprop(t->asize) != Olit)

+				fatal(t->asize, "nonconstant array size near %s\n", ctxstr(t->asize));

 		} else if (t->type == Tystruct) {

 			inaggr++;

 			for (i = 0; i < t->nmemb; i++)

--- a/parse/parse.h

+++ b/parse/parse.h

@@ -573,5 +573,6 @@

 extern char **incpaths;

 extern size_t nincpaths;

 extern char *localincpath;

+extern size_t (*sizefn)(Node *n);

 void yyerror(const char *s);