Commit beae932e0f8ab39f97a142282c67c83c979f8be1 | zig

author	Andrew Kelley <andrew@ziglang.org> 2020-04-08 21:02:50-04:00
committer	GitHub <noreply@github.com> 2020-04-08 21:02:50-04:00
log	beae932e0f8ab39f97a142282c67c83c979f8be1
tree	81390dd27b0f0290d113cc4221ddb8416be55bd1
parent	c3afaa1f580510cf2ef304ce65d78a86314b38a5
parent	b1e44adcba55e3839a3676db83ff61c344f3bbad
signature	Signed by PGP key 4AEE18F83AFDEB23

Merge pull request #4975 from Vexu/param-reassign

Fix missing compile error on assign to slice and array parameters

4 files changed, 57 insertions(+), 4 deletions(-)

build.zig
src
- ir.cpp
test
- compile_errors.zig
- tests.zig

build.zig+3-2

 @@ -225,10 +225,11 @@ fn findLLVM(b: *Builder, llvm_config_exe: []const u8) !LibraryDep {
                 if (fs.path.isAbsolute(lib_arg)) {
                     try result.libs.append(lib_arg);
                 } else {
+                    var lib_arg_copy = lib_arg;
                     if (mem.endsWith(u8, lib_arg, ".lib")) {
-                        lib_arg = lib_arg[0 .. lib_arg.len - 4];
+                        lib_arg_copy = lib_arg[0 .. lib_arg.len - 4];
                     }
-                    try result.system_libs.append(lib_arg);
+                    try result.system_libs.append(lib_arg_copy);
                 }
             }
         }

src/ir.cpp+17-1

 @@ -23556,10 +23556,14 @@ static IrInstGen *ir_analyze_instruction_container_init_list(IrAnalyze *ira,
     IrInstGen *result_loc = instruction->result_loc->child;
     if (type_is_invalid(result_loc->value->type))
         return result_loc;
     ir_assert(result_loc->value->type->id == ZigTypeIdPointer, &instruction->base.base);
+    if (result_loc->value->type->data.pointer.is_const) {
+        ir_add_error(ira, &instruction->base.base, buf_sprintf("cannot assign to constant"));
+        return ira->codegen->invalid_inst_gen;
+    }
     ZigType *container_type = result_loc->value->type->data.pointer.child_type;
     size_t elem_count = instruction->item_count;
     if (is_slice(container_type)) {
 @@ -23710,6 +23714,11 @@ static IrInstGen *ir_analyze_instruction_container_init_fields(IrAnalyze *ira,
         return result_loc;
     ir_assert(result_loc->value->type->id == ZigTypeIdPointer, &instruction->base.base);
+    if (result_loc->value->type->data.pointer.is_const) {
+        ir_add_error(ira, &instruction->base.base, buf_sprintf("cannot assign to constant"));
+        return ira->codegen->invalid_inst_gen;
+    }
     ZigType *container_type = result_loc->value->type->data.pointer.child_type;
     return ir_analyze_container_init_fields(ira, &instruction->base.base, container_type,
 @@ -27179,6 +27188,13 @@ done_with_return_type:
             if (type_is_invalid(result_loc->value->type) || result_loc->value->type->id == ZigTypeIdUnreachable) {
                 return result_loc;
             }
+            ir_assert(result_loc->value->type->id == ZigTypeIdPointer, &instruction->base.base);
+            if (result_loc->value->type->data.pointer.is_const) {
+                ir_add_error(ira, &instruction->base.base, buf_sprintf("cannot assign to constant"));
+                return ira->codegen->invalid_inst_gen;
+            }
             IrInstGen *dummy_value = ir_const(ira, &instruction->base.base, return_type);
             dummy_value->value->special = ConstValSpecialRuntime;
             IrInstGen *dummy_result = ir_implicit_cast2(ira, &instruction->base.base,

test/compile_errors.zig+36

...	@@ -2,6 +2,42 @@ const tests = @import("tests.zig");	...	@@ -2,6 +2,42 @@ const tests = @import("tests.zig");
2	const std = @import("std");	2	const std = @import("std");
3		3
4	pub fn addCases(cases: *tests.CompileErrorContext) void {	4	pub fn addCases(cases: *tests.CompileErrorContext) void {
		5	cases.addTest("reassign to array parameter",
		6	\\fn reassign(a: [3]f32) void {
		7	\\ a = [3]f32{4, 5, 6};
		8	\\}
		9	\\export fn entry() void {
		10	\\ reassign(.{1, 2, 3});
		11	\\}
		12	, &[_][]const u8{
		13	"tmp.zig:2:15: error: cannot assign to constant"
		14	});
		15
		16	cases.addTest("reassign to slice parameter",
		17	\\pub fn reassign(s: []const u8) void {
		18	\\ s = s[0..];
		19	\\}
		20	\\export fn entry() void {
		21	\\ reassign("foo");
		22	\\}
		23	, &[_][]const u8{
		24	"tmp.zig:2:10: error: cannot assign to constant"
		25	});
		26
		27	cases.addTest("reassign to struct parameter",
		28	\\const S = struct {
		29	\\ x: u32,
		30	\\};
		31	\\fn reassign(s: S) void {
		32	\\ s = S{.x = 2};
		33	\\}
		34	\\export fn entry() void {
		35	\\ reassign(S{.x = 3});
		36	\\}
		37	, &[_][]const u8{
		38	"tmp.zig:5:10: error: cannot assign to constant"
		39	});
		40
5	cases.addTest("reference to const data",	41	cases.addTest("reference to const data",
6	\\export fn foo() void {	42	\\export fn foo() void {
7	\\ var ptr = &[_]u8{0,0,0,0};	43	\\ var ptr = &[_]u8{0,0,0,0};

test/tests.zig+1-1

...	@@ -612,7 +612,7 @@ pub const StackTracesContext = struct {	...	@@ -612,7 +612,7 @@ pub const StackTracesContext = struct {
612		612
613	const stdout = child.stdout.?.inStream().readAllAlloc(b.allocator, max_stdout_size) catch unreachable;	613	const stdout = child.stdout.?.inStream().readAllAlloc(b.allocator, max_stdout_size) catch unreachable;
614	defer b.allocator.free(stdout);	614	defer b.allocator.free(stdout);
615	const stderr = child.stderr.?.inStream().readAllAlloc(b.allocator, max_stdout_size) catch unreachable;	615	var stderr = child.stderr.?.inStream().readAllAlloc(b.allocator, max_stdout_size) catch unreachable;
616	defer b.allocator.free(stderr);	616	defer b.allocator.free(stderr);
617		617
618	const term = child.wait() catch \|err\| {	618	const term = child.wait() catch \|err\| {