Commit 6664679c8c1d24e929630daf8392ca09620d4a94 | zig

author	Veikka Tuominen <git@vexu.eu> 2021-06-13 10:56:54+03:00
committer	Veikka Tuominen <git@vexu.eu> 2021-06-13 15:23:31+03:00
log	6664679c8c1d24e929630daf8392ca09620d4a94
tree	42c4fa816d5b802a0e9609580c86c22eaf98a36a
parent	540b52931aeeee7c72c73361118d07ab986cf048

translate-c: don't bother with unwrapping pointers

Dereferencing a c pointer implicitly includes an unwrap,
manually adding it just causes bugs.

4 files changed, 36 insertions(+), 10 deletions(-)

src
- translate_c.zig
- translate_c
  - ast.zig
test
- run_translated_c.zig
- translate_c.zig

src/translate_c.zig+7-5

...	...	@@ -1438,7 +1438,7 @@ fn transSimpleOffsetOfExpr(
1438	1438	}
1439	1439	}
1440	1440	}
1441		return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "Failed to translate simple OffsetOfExpr", .{});
	1441	return fail(c, error.UnsupportedTranslation, expr.getBeginLoc(), "failed to translate simple OffsetOfExpr", .{});
1442	1442	}
1443	1443
1444	1444	fn transOffsetOfExpr(
...	...	@@ -2619,7 +2619,7 @@ fn transInitListExpr(
2619	2619	const source_loc = @ptrCast(*const clang.Expr, expr).getBeginLoc();
2620	2620
2621	2621	if (qualTypeWasDemotedToOpaque(c, qt)) {
2622		return fail(c, error.UnsupportedTranslation, source_loc, "Cannot initialize opaque type", .{});
	2622	return fail(c, error.UnsupportedTranslation, source_loc, "cannot initialize opaque type", .{});
2623	2623	}
2624	2624
2625	2625	if (qual_type.isRecordType()) {
...	...	@@ -3408,7 +3408,7 @@ fn transUnaryExprOrTypeTraitExpr(
3408	3408	c,
3409	3409	error.UnsupportedTranslation,
3410	3410	loc,
3411		"Unsupported type trait kind {}",
	3411	"unsupported type trait kind {}",
3412	3412	.{kind},
3413	3413	),
3414	3414	}
...	...	@@ -3450,13 +3450,15 @@ fn transUnaryOperator(c: Context, scope: Scope, stmt: *const clang.UnaryOperat
3450	3450	return Tag.address_of.create(c.arena, try transExpr(c, scope, op_expr, used));
3451	3451	},
3452	3452	.Deref => {
	3453	if (qualTypeWasDemotedToOpaque(c, stmt.getType()))
	3454	return fail(c, error.UnsupportedTranslation, stmt.getBeginLoc(), "cannot dereference opaque type", .{});
	3455
3453	3456	const node = try transExpr(c, scope, op_expr, used);
3454	3457	var is_ptr = false;
3455	3458	const fn_ty = qualTypeGetFnProto(op_expr.getType(), &is_ptr);
3456	3459	if (fn_ty != null and is_ptr)
3457	3460	return node;
3458		const unwrapped = try Tag.unwrap.create(c.arena, node);
3459		return Tag.deref.create(c.arena, unwrapped);
	3461	return Tag.deref.create(c.arena, node);
3460	3462	},
3461	3463	.Plus => return transExpr(c, scope, op_expr, used),
3462	3464	.Minus => {

src/translate_c/ast.zig+1-1

...	...	@@ -2294,7 +2294,6 @@ fn renderNodeGrouped(c: *Context, node: Node) !NodeIndex {
2294	2294	.single_pointer,
2295	2295	.unwrap,
2296	2296	.deref,
2297		.address_of,
2298	2297	.not,
2299	2298	.negate,
2300	2299	.negate_wrap,
...	...	@@ -2349,6 +2348,7 @@ fn renderNodeGrouped(c: *Context, node: Node) !NodeIndex {
2349	2348	.container_init,
2350	2349	.container_init_dot,
2351	2350	.block,
	2351	.address_of,
2352	2352	=> return c.addNode(.{
2353	2353	.tag = .grouped_expression,
2354	2354	.main_token = try c.addToken(.l_paren, "("),

test/run_translated_c.zig+10

...	...	@@ -3,6 +3,16 @@ const tests = @import("tests.zig");
3	3	const nl = std.cstr.line_sep;
4	4
5	5	pub fn addCases(cases: *tests.RunTranslatedCContext) void {
	6	cases.add("dereference address of",
	7	\\#include <stdlib.h>
	8	\\int main(void) {
	9	\\ int i = 0;
	10	\\ *&i = 42;
	11	\\ if (i != 42) abort();
	12	\\ return 0;
	13	\\}
	14	, "");
	15
6	16	cases.add("division of floating literals",
7	17	\\#define _NO_CRT_STDIO_INLINE 1
8	18	\\#include <stdio.h>

test/translate_c.zig+18-4

...	...	@@ -1515,7 +1515,7 @@ pub fn addCases(cases: *tests.TranslateCContext) void {
1515	1515	, &[_][]const u8{
1516	1516	\\pub export fn foo() void {
1517	1517	\\ var x: [*c]c_int = undefined;
1518		\\ x.?.* = 1;
	1518	\\ x.* = 1;
1519	1519	\\}
1520	1520	});
1521	1521
...	...	@@ -1529,7 +1529,7 @@ pub fn addCases(cases: *tests.TranslateCContext) void {
1529	1529	\\pub export fn foo() c_int {
1530	1530	\\ var x: c_int = 1234;
1531	1531	\\ var ptr: [*c]c_int = &x;
1532		\\ return ptr.?.*;
	1532	\\ return ptr.*;
1533	1533	\\}
1534	1534	});
1535	1535
...	...	@@ -3243,7 +3243,7 @@ pub fn addCases(cases: *tests.TranslateCContext) void {
3243	3243	\\ const tmp_2 = ref.*;
3244	3244	\\ ref.* += 1;
3245	3245	\\ break :blk_1 tmp_2;
3246		\\ }).?.* = tmp;
	3246	\\ }).* = tmp;
3247	3247	\\ break :blk tmp;
3248	3248	\\ };
3249	3249	\\}
...	...	@@ -3583,12 +3583,26 @@ pub fn addCases(cases: *tests.TranslateCContext) void {
3583	3583	\\ struct my_struct S = {.a = 1, .b = 2};
3584	3584	\\}
3585	3585	, &[_][]const u8{
3586		\\warning: Cannot initialize opaque type
	3586	\\warning: cannot initialize opaque type
3587	3587	,
3588	3588	\\warning: unable to translate function, demoted to extern
3589	3589	\\pub extern fn initialize() void;
3590	3590	});
3591	3591
	3592	cases.add("Demote function that dereferences opaque type",
	3593	\\struct my_struct {
	3594	\\ unsigned a: 1;
	3595	\\};
	3596	\\void deref(struct my_struct *s) {
	3597	\\ *s;
	3598	\\}
	3599	, &[_][]const u8{
	3600	\\warning: cannot dereference opaque type
	3601	,
	3602	\\warning: unable to translate function, demoted to extern
	3603	\\pub extern fn deref(arg_s: ?*struct_my_struct) void;
	3604	});
	3605
3592	3606	cases.add("Function prototype declared within function",
3593	3607	\\int foo(void) {
3594	3608	\\ extern int bar(int, int);