Commit d000e53b291afc40da7d676553f1c9685a38f169 | zig

author	Alex Rønne Petersen <alex@alexrp.com> 2025-05-20 07:48:35+02:00
committer	GitHub <noreply@github.com> 2025-05-20 07:48:35+02:00
log	d000e53b291afc40da7d676553f1c9685a38f169
tree	b8ed7fe4dbecdc6dc6d6a297fa57545c057f52c0
parent	b27c5fbbdeeab12359c7f5bca0fe15fb0be9424e
parent	b0c10e2262b975743932258710e3fca47113d16e
signature	Signed by PGP key B5690EEEBB952194

Merge pull request #23923 from alexrp/compiler-rt-symbols

Use hidden visibility in compiler-rt and libzigc except when testing

10 files changed, 141 insertions(+), 133 deletions(-)

build.zig
lib
- c
  - common.zig
- compiler_rt
- std
  - leb128.zig
test
- tests.zig
tools
- gen_outline_atomics.zig

build.zig+2-1

...	@@ -437,7 +437,8 @@ pub fn build(b: *std.Build) !void {	...	@@ -437,7 +437,8 @@ pub fn build(b: *std.Build) !void {
437	.skip_non_native = skip_non_native,	437	.skip_non_native = skip_non_native,
438	.skip_libc = skip_libc,	438	.skip_libc = skip_libc,
439	.use_llvm = use_llvm,	439	.use_llvm = use_llvm,
440	.max_rss = 2 * 1024 * 1024 * 1024,	440	// 2262585344 was observed on an x86_64-linux-gnu host.
		441	.max_rss = 2488843878,
441	}));	442	}));
442		443
443	test_modules_step.dependOn(tests.addModuleTests(b, .{	444	test_modules_step.dependOn(tests.addModuleTests(b, .{

lib/c/common.zig+1-1

...	@@ -9,7 +9,7 @@ else	...	@@ -9,7 +9,7 @@ else
9	/// Determines the symbol's visibility to other objects.	9	/// Determines the symbol's visibility to other objects.
10	/// For WebAssembly this allows the symbol to be resolved to other modules, but will not	10	/// For WebAssembly this allows the symbol to be resolved to other modules, but will not
11	/// export it to the host runtime.	11	/// export it to the host runtime.
12	pub const visibility: std.builtin.SymbolVisibility = if (builtin.cpu.arch.isWasm() and linkage != .internal)	12	pub const visibility: std.builtin.SymbolVisibility = if (linkage != .internal)
13	.hidden	13	.hidden
14	else	14	else
15	.default;	15	.default;

lib/compiler_rt/aarch64_outline_atomics.zig+101-101

lib/compiler_rt/clear_cache.zig+3-4

 @@ -2,7 +2,8 @@ const std = @import("std");
 const builtin = @import("builtin");
 const arch = builtin.cpu.arch;
 const os = builtin.os.tag;
-pub const panic = @import("common.zig").panic;
+const common = @import("common.zig");
+pub const panic = common.panic;
 // Ported from llvm-project d32170dbd5b0d54436537b6b75beaf44324e0c28
 @@ -174,10 +175,8 @@ fn clear_cache(start: usize, end: usize) callconv(.c) void {
     }
 }
-const linkage = if (builtin.is_test) std.builtin.GlobalLinkage.internal else std.builtin.GlobalLinkage.weak;
 fn exportIt() void {
-    @export(&clear_cache, .{ .name = "__clear_cache", .linkage = linkage });
+    @export(&clear_cache, .{ .name = "__clear_cache", .linkage = common.linkage, .visibility = common.visibility });
 }
 // Darwin-only

lib/compiler_rt/common.zig+7-2

 @@ -3,6 +3,9 @@ const builtin = @import("builtin");
 const native_endian = builtin.cpu.arch.endian();
 const ofmt_c = builtin.object_format == .c;
+/// For now, we prefer weak linkage because some of the routines we implement here may also be
+/// provided by system/dynamic libc. Eventually we should be more disciplined about this on a
+/// per-symbol, per-target basis: https://github.com/ziglang/zig/issues/11883
 pub const linkage: std.builtin.GlobalLinkage = if (builtin.is_test)
     .internal
 else if (ofmt_c)
 @@ -13,8 +16,10 @@ else
 /// Determines the symbol's visibility to other objects.
 /// For WebAssembly this allows the symbol to be resolved to other modules, but will not
 /// export it to the host runtime.
-pub const visibility: std.builtin.SymbolVisibility =
+pub const visibility: std.builtin.SymbolVisibility = if (linkage != .internal)
-    if (builtin.target.cpu.arch.isWasm() and linkage != .internal) .hidden else .default;
+    .hidden
+else
+    .default;
 pub const PreferredLoadStoreElement = element: {
     if (std.simd.suggestVectorLength(u8)) |vec_size| {

lib/compiler_rt/os_version_check.zig+2-2

...	@@ -1,7 +1,7 @@	...	@@ -1,7 +1,7 @@
1	const std = @import("std");	1	const std = @import("std");
2	const testing = std.testing;	2	const testing = std.testing;
3	const builtin = @import("builtin");	3	const builtin = @import("builtin");
4	const linkage: std.builtin.GlobalLinkage = if (builtin.is_test) .internal else .weak;	4	const common = @import("common.zig");
5	const panic = @import("common.zig").panic;	5	const panic = @import("common.zig").panic;
6		6
7	const have_availability_version_check = builtin.os.tag.isDarwin() and	7	const have_availability_version_check = builtin.os.tag.isDarwin() and
...	@@ -9,7 +9,7 @@ const have_availability_version_check = builtin.os.tag.isDarwin() and	...	@@ -9,7 +9,7 @@ const have_availability_version_check = builtin.os.tag.isDarwin() and
9		9
10	comptime {	10	comptime {
11	if (have_availability_version_check) {	11	if (have_availability_version_check) {
12	@export(&__isPlatformVersionAtLeast, .{ .name = "__isPlatformVersionAtLeast", .linkage = linkage });	12	@export(&__isPlatformVersionAtLeast, .{ .name = "__isPlatformVersionAtLeast", .linkage = common.linkage, .visibility = common.visibility });
13	}	13	}
14	}	14	}
15		15

lib/compiler_rt/stack_probe.zig+8-9

 @@ -1,28 +1,27 @@
 const std = @import("std");
 const builtin = @import("builtin");
+const common = @import("common.zig");
 const os_tag = builtin.os.tag;
 const arch = builtin.cpu.arch;
 const abi = builtin.abi;
 const is_test = builtin.is_test;
-const linkage: std.builtin.GlobalLinkage = if (builtin.is_test) .internal else .weak;
+pub const panic = common.panic;
-const strong_linkage: std.builtin.GlobalLinkage = if (builtin.is_test) .internal else .strong;
-pub const panic = @import("common.zig").panic;
 comptime {
     if (builtin.os.tag == .windows) {
         // Default stack-probe functions emitted by LLVM
         if (builtin.target.isMinGW()) {
-            @export(&_chkstk, .{ .name = "_alloca", .linkage = linkage });
+            @export(&_chkstk, .{ .name = "_alloca", .linkage = common.linkage, .visibility = common.visibility });
-            @export(&___chkstk_ms, .{ .name = "___chkstk_ms", .linkage = linkage });
+            @export(&___chkstk_ms, .{ .name = "___chkstk_ms", .linkage = common.linkage, .visibility = common.visibility });
             if (arch == .thumb or arch == .aarch64) {
-                @export(&__chkstk, .{ .name = "__chkstk", .linkage = linkage });
+                @export(&__chkstk, .{ .name = "__chkstk", .linkage = common.linkage, .visibility = common.visibility });
             }
         } else if (!builtin.link_libc) {
             // This symbols are otherwise exported by MSVCRT.lib
-            @export(&_chkstk, .{ .name = "_chkstk", .linkage = linkage });
+            @export(&_chkstk, .{ .name = "_chkstk", .linkage = common.linkage, .visibility = common.visibility });
-            @export(&__chkstk, .{ .name = "__chkstk", .linkage = linkage });
+            @export(&__chkstk, .{ .name = "__chkstk", .linkage = common.linkage, .visibility = common.visibility });
         }
     }
 @@ -30,7 +29,7 @@ comptime {
         .x86,
         .x86_64,
         => {
-            @export(&zig_probe_stack, .{ .name = "__zig_probe_stack", .linkage = linkage });
+            @export(&zig_probe_stack, .{ .name = "__zig_probe_stack", .linkage = common.linkage, .visibility = common.visibility });
         },
         else => {},
     }

lib/std/leb128.zig+5

...	@@ -1,3 +1,4 @@	...	@@ -1,3 +1,4 @@
		1	const builtin = @import("builtin");
1	const std = @import("std");	2	const std = @import("std");
2	const testing = std.testing;	3	const testing = std.testing;
3		4
...	@@ -432,6 +433,8 @@ fn test_write_leb128(value: anytype) !void {	...	@@ -432,6 +433,8 @@ fn test_write_leb128(value: anytype) !void {
432	}	433	}
433		434
434	test "serialize unsigned LEB128" {	435	test "serialize unsigned LEB128" {
		436	if (builtin.cpu.arch == .x86 and builtin.abi == .musl and builtin.link_mode == .dynamic) return error.SkipZigTest;
		437
435	const max_bits = 18;	438	const max_bits = 18;
436		439
437	comptime var t = 0;	440	comptime var t = 0;
...	@@ -446,6 +449,8 @@ test "serialize unsigned LEB128" {	...	@@ -446,6 +449,8 @@ test "serialize unsigned LEB128" {
446	}	449	}
447		450
448	test "serialize signed LEB128" {	451	test "serialize signed LEB128" {
		452	if (builtin.cpu.arch == .x86 and builtin.abi == .musl and builtin.link_mode == .dynamic) return error.SkipZigTest;
		453
449	// explicitly test i0 because starting `t` at 0	454	// explicitly test i0 because starting `t` at 0
450	// will break the while loop	455	// will break the while loop
451	try test_write_leb128(@as(i0, 0));	456	try test_write_leb128(@as(i0, 0));

test/tests.zig+10-11

...	@@ -296,17 +296,16 @@ const test_targets = blk: {	...	@@ -296,17 +296,16 @@ const test_targets = blk: {
296	},	296	},
297	.link_libc = true,	297	.link_libc = true,
298	},	298	},
299	// https://github.com/ziglang/zig/issues/7935	299	.{
300	// .{	300	.target = .{
301	// .target = .{	301	.cpu_arch = .x86,
302	// .cpu_arch = .x86,	302	.os_tag = .linux,
303	// .os_tag = .linux,	303	.abi = .musl,
304	// .abi = .musl,	304	},
305	// },	305	.linkage = .dynamic,
306	// .linkage = .dynamic,	306	.link_libc = true,
307	// .link_libc = true,	307	.extra_target = true,
308	// .extra_target = true,	308	},
309	// },
310	.{	309	.{
311	.target = .{	310	.target = .{
312	.cpu_arch = .x86,	311	.cpu_arch = .x86,

tools/gen_outline_atomics.zig+2-2

...	@@ -24,7 +24,7 @@ pub fn main() !void {	...	@@ -24,7 +24,7 @@ pub fn main() !void {
24	\\//! This file is generated by tools/gen_outline_atomics.zig.	24	\\//! This file is generated by tools/gen_outline_atomics.zig.
25	\\const builtin = @import("builtin");	25	\\const builtin = @import("builtin");
26	\\const std = @import("std");	26	\\const std = @import("std");
27	\\const linkage = @import("./common.zig").linkage;	27	\\const common = @import("common.zig");
28	\\const always_has_lse = std.Target.aarch64.featureSetHas(builtin.cpu.features, .lse);	28	\\const always_has_lse = std.Target.aarch64.featureSetHas(builtin.cpu.features, .lse);
29	\\	29	\\
30	\\/// This default is overridden at runtime after inspecting CPU properties.	30	\\/// This default is overridden at runtime after inspecting CPU properties.
...	@@ -48,7 +48,7 @@ pub fn main() !void {	...	@@ -48,7 +48,7 @@ pub fn main() !void {
48	@tagName(op), n.toBytes(), @tagName(order),	48	@tagName(op), n.toBytes(), @tagName(order),
49	});	49	});
50	try writeFunction(arena, w, name, op, n, order);	50	try writeFunction(arena, w, name, op, n, order);
51	try footer.writer().print(" @export(&{s}, .{{ .name = \"{s}\", .linkage = linkage }});\n", .{	51	try footer.writer().print(" @export(&{s}, .{{ .name = \"{s}\", .linkage = common.linkage, .visibility = common.visibility }});\n", .{
52	name, name,	52	name, name,
53	});	53	});
54	}	54	}