ww: implement package initialization

selfhost/cmd/wcc/cgen.ww

@@ -509,6 +509,7 @@ type cgen = struct {
 	// root entry stays bare. Like sepmode, NOT reset by cgeninit (per-fn).
 	// Symmetric with cstage Cg.sep_isdep.
 	sepisdep: i32,
+	initdispatchsymbol: str,	// root-owned complete package-init schedule
 };
 
 // Top-level mutable `let` registry. Mirrors cmd/w6c/cgen.c LetVar.
@@ -741,6 +742,17 @@ fn localfind(c: *cgen, name: str) i32 = {
 let cgoutstream: memio.stream;
 let cgoutmode:   i32 = 0;
 let cgoutinit:   i32 = 0;
+let cgwritefailed: i32 = 0;
+
+fn cgwrite(p: *u8, n: u64) void = {
+	if (cgwritefailed != 0) { return; };
+	match (os.writeall(1i32, p, n)) {
+	case let wrote: i64 => {
+		if (wrote < 0 || (wrote: u64) != n) { cgwritefailed = 1; };
+	};
+	case let e: os.oserror => cgwritefailed = 1;
+	};
+};
 
 fn cgout_enable() void = {
 	if (cgoutinit == 0) {
@@ -754,7 +766,7 @@ fn cgout_disable() void = { cgoutmode = 0; };
 
 fn cgout_flush() void = {
 	if (cgoutstream.pos > 0) {
-		os.write(1, cgoutstream.ptr, cgoutstream.pos: u64);
+		cgwrite(cgoutstream.ptr, cgoutstream.pos: u64);
 		memio.reset(&cgoutstream);
 	};
 };
@@ -769,7 +781,7 @@ fn emitbytes(p: *u8, n: u64) void = {
 		// lib/log/log.ww stdprintln. #94 fold-eFinal.
 		io.write(&cgoutstream.vt, buf);
 	} else {
-		os.write(1, p, n);
+		cgwrite(p, n);
 	};
 };
 
@@ -2894,6 +2906,35 @@ fn emittupledata(c: *cgen, name: str, module: str, tt: *syntax.node, rhs: *synta
 	return true;
 };
 
+fn emitinitbackings(n: *syntax.node) void = {
+	for (n != nil) {
+		if (n.kind == syntax.nkind.N_ARRLIT && n.linksym.len > 0) {
+			let u: *syntax.tinfo = tichase(n.type_: *syntax.tinfo);
+			if (u == nil || u.kind != syntax.tykind.TY_ARRAY) {
+				let msg: str = "runtime package slice backing has no array type\n";
+				os.write(2, msg.ptr, msg.len: u64);
+				os.exit(1);
+			};
+			emitline("DATAW ");
+			emitbytes(n.linksym.ptr, n.linksym.len: u64);
+			emitline("(SB),\"");
+			let count: u64 = u.size;
+			if (count == 0u64) { count = 1u64; };
+			let i: u64 = 0u64;
+			for (i < count) { emitdatawbyte(0u8); i += 1u64; };
+			emitline("\"\n");
+		};
+		emitinitbackings(n.attr);
+		emitinitbackings(n.lhs);
+		emitinitbackings(n.rhs);
+		emitinitbackings(n.cond);
+		emitinitbackings(n.body);
+		emitinitbackings(n.els);
+		emitinitbackings(n.list);
+		n = n.next;
+	};
+};
+
 fn emitletdataw(c: *cgen, file: *syntax.node) void = {
 	let savedmod: str = c.curmod;
 	let savedsource: i32 = c.cursource;
@@ -3458,6 +3499,10 @@ fn collectfnrets(c: *cgen, file: *syntax.node) void = {
 	let d: *syntax.node = file.list;
 	for (d != nil) {
 		if (d.kind == syntax.nkind.N_FNDECL) {
+			if (d.initfn != 0 || d.initsynthetic != 0) {
+				d = d.next;
+				continue;
+			};
 			let f: *fnret = alloc(fnret{fname=d.str, fmod=d.nmod, rtype=d.lhs, params=d.list, frnext=c.fnrets})!;
 			c.fnrets = f;
 		};
@@ -3788,12 +3833,16 @@ fn collectmods(c: *cgen, file: *syntax.node) void = {
 	let d: *syntax.node = file.list;
 	for (d != nil) {
 		// M1 #22: record alias→path for the qualified-ref hint.
-		if (d.kind == syntax.nkind.N_USE) {
+		if (d.kind == syntax.nkind.N_USE && d.useblank == 0) {
 			if (d.usepath.len > 0) {
 					let um: *modent = alloc(modent{mname=d.str, nmod=d.usepath, omod=d.nmod, sourceid=d.sourceid, mnext=c.uses})!;
 				c.uses = um;
 			};
 		};
+		if (d.initfn != 0 || d.initsynthetic != 0) {
+			d = d.next;
+			continue;
+		};
 		// Mirror collectfnrets' shape exactly (plain prepend in one
 		// branch). Earlier nested-if/early-return variants tickled a
 		// wwstage cgen bug that dropped most prepends.
@@ -3988,6 +4037,10 @@ fn fficollect(c: *cgen, file: *syntax.node) void = {
 	let d: *syntax.node = file.list;
 	for (d != nil) {
 		if (d.kind == syntax.nkind.N_FNDECL) {
+			if (d.initfn != 0 || d.initsynthetic != 0) {
+				d = d.next;
+				continue;
+			};
 			let a: *syntax.node = d.attr;
 			for (a != nil) {
 				if (a.kind == syntax.nkind.N_ATTR) {