[llvm-branch-commits] [libc] [libc][annex_k] Add errno_t. (PR #163094)
Muhammad Bassiouni via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Sat Oct 18 08:02:23 PDT 2025
https://github.com/bassiounix updated https://github.com/llvm/llvm-project/pull/163094
>From c39276700cd5da9980ea022b121a1f74fdf27f0c Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Sun, 12 Oct 2025 22:18:17 +0300
Subject: [PATCH 1/5] [libc][annex_k] Add errno_t.
---
libc/hdr/types/CMakeLists.txt | 9 +++++++++
libc/hdr/types/errno_t.h | 18 ++++++++++++++++++
libc/include/CMakeLists.txt | 1 +
libc/include/errno.h.def | 2 ++
libc/include/llvm-libc-types/CMakeLists.txt | 2 ++
libc/include/llvm-libc-types/errno_t.h | 18 ++++++++++++++++++
6 files changed, 50 insertions(+)
create mode 100644 libc/hdr/types/errno_t.h
create mode 100644 libc/include/llvm-libc-types/errno_t.h
diff --git a/libc/hdr/types/CMakeLists.txt b/libc/hdr/types/CMakeLists.txt
index 225843924c243..8ec2926ee16fc 100644
--- a/libc/hdr/types/CMakeLists.txt
+++ b/libc/hdr/types/CMakeLists.txt
@@ -162,6 +162,15 @@ add_proxy_header_library(
libc.include.fcntl
)
+add_proxy_header_library(
+ errno_t
+ HDRS
+ errno_t.h
+ FULL_BUILD_DEPENDS
+ libc.include.llvm-libc-types.errno_t
+ libc.include.errno
+)
+
add_proxy_header_library(
fenv_t
HDRS
diff --git a/libc/hdr/types/errno_t.h b/libc/hdr/types/errno_t.h
new file mode 100644
index 0000000000000..91706b05c9155
--- /dev/null
+++ b/libc/hdr/types/errno_t.h
@@ -0,0 +1,18 @@
+//===-- Proxy for errno_t -------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_HDR_TYPES_ERRNO_T_H
+#define LLVM_LIBC_HDR_TYPES_ERRNO_T_H
+
+#define LIBC_HAS_ANNEX_K
+
+#include "include/llvm-libc-types/errno_t.h"
+
+#undef LIBC_HAS_ANNEX_K
+
+#endif // LLVM_LIBC_HDR_TYPES_ERRNO_T_H
diff --git a/libc/include/CMakeLists.txt b/libc/include/CMakeLists.txt
index 81360aac984e0..c70d1190e8342 100644
--- a/libc/include/CMakeLists.txt
+++ b/libc/include/CMakeLists.txt
@@ -302,6 +302,7 @@ add_header_macro(
DEPENDS
.llvm-libc-macros.generic_error_number_macros
.llvm-libc-macros.error_number_macros
+ .llvm-libc-types.errno_t
)
add_header_macro(
diff --git a/libc/include/errno.h.def b/libc/include/errno.h.def
index aa1f6c9e48444..35341c60e38b2 100644
--- a/libc/include/errno.h.def
+++ b/libc/include/errno.h.def
@@ -33,4 +33,6 @@ __END_C_DECLS
#define errno (*__llvm_libc_errno())
+#include "llvm-libc-types/errno_t.h"
+
#endif // LLVM_LIBC_ERRNO_H
diff --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
index 5f506c4d25c9b..cfd0eabc42d5e 100644
--- a/libc/include/llvm-libc-types/CMakeLists.txt
+++ b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -298,3 +298,5 @@ add_header(EFI_SYSTEM_TABLE
.EFI_TABLE_HEADER
.char16_t
)
+
+add_header(errno_t HDR errno_t.h)
diff --git a/libc/include/llvm-libc-types/errno_t.h b/libc/include/llvm-libc-types/errno_t.h
new file mode 100644
index 0000000000000..f99fe1266ccd1
--- /dev/null
+++ b/libc/include/llvm-libc-types/errno_t.h
@@ -0,0 +1,18 @@
+//===-- Definition of type errno_t ----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
+#define LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
+
+#ifdef LIBC_HAS_ANNEX_K
+
+typedef int errno_t;
+
+#endif // LIBC_HAS_ANNEX_K
+
+#endif // LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
>From e74324e7150b8fab201f8407bfa3cdb23d2ae184 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Tue, 14 Oct 2025 00:44:08 +0300
Subject: [PATCH 2/5] change location of errno_t
---
libc/include/llvm-libc-types/CMakeLists.txt | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
index cfd0eabc42d5e..e8b3ae8c08a90 100644
--- a/libc/include/llvm-libc-types/CMakeLists.txt
+++ b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -29,6 +29,7 @@ add_header(double_t HDR double_t.h)
add_header(DIR HDR DIR.h)
add_header(dev_t HDR dev_t.h)
add_header(div_t HDR div_t.h)
+add_header(errno_t HDR errno_t.h)
add_header(ldiv_t HDR ldiv_t.h)
add_header(lldiv_t HDR lldiv_t.h)
add_header(FILE HDR FILE.h)
@@ -298,5 +299,3 @@ add_header(EFI_SYSTEM_TABLE
.EFI_TABLE_HEADER
.char16_t
)
-
-add_header(errno_t HDR errno_t.h)
>From 434e23c33d47f12808c6804f37c4bc091010fc71 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Fri, 17 Oct 2025 01:17:20 +0300
Subject: [PATCH 3/5] add clarifying comment about LIBC_HAS_ANNEX_K
---
libc/include/llvm-libc-types/errno_t.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/libc/include/llvm-libc-types/errno_t.h b/libc/include/llvm-libc-types/errno_t.h
index f99fe1266ccd1..a37b5dece2c35 100644
--- a/libc/include/llvm-libc-types/errno_t.h
+++ b/libc/include/llvm-libc-types/errno_t.h
@@ -9,6 +9,9 @@
#ifndef LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
#define LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
+// LIBC_HAS_ANNEX_K is a necessary check guard here because errno_t is only
+// defined when Annex K is enabled. We use LIBC_HAS_ANNEX_K internally to
+// indicate whether Annex K is enabled or not.
#ifdef LIBC_HAS_ANNEX_K
typedef int errno_t;
>From 7a54e665d45b3bdec00938699674575165798fd6 Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Fri, 17 Oct 2025 01:57:02 +0300
Subject: [PATCH 4/5] add errno_t to hdrgen
---
libc/include/errno.h.def | 2 --
libc/include/errno.yaml | 3 ++-
2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/libc/include/errno.h.def b/libc/include/errno.h.def
index 35341c60e38b2..aa1f6c9e48444 100644
--- a/libc/include/errno.h.def
+++ b/libc/include/errno.h.def
@@ -33,6 +33,4 @@ __END_C_DECLS
#define errno (*__llvm_libc_errno())
-#include "llvm-libc-types/errno_t.h"
-
#endif // LLVM_LIBC_ERRNO_H
diff --git a/libc/include/errno.yaml b/libc/include/errno.yaml
index 188a9fa1211a1..86afd2f03b20c 100644
--- a/libc/include/errno.yaml
+++ b/libc/include/errno.yaml
@@ -5,7 +5,8 @@ standards:
- Linux
- POSIX
macros: []
-types: []
+types:
+ - type_name: errno_t
enums: []
objects: []
functions: []
>From 8bcde7fb5cbccaea50b9cbc82dda7b1fc9811f4b Mon Sep 17 00:00:00 2001
From: bassiounix <muhammad.m.bassiouni at gmail.com>
Date: Fri, 17 Oct 2025 02:06:05 +0300
Subject: [PATCH 5/5] change clarifying comment
---
libc/include/llvm-libc-types/errno_t.h | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/libc/include/llvm-libc-types/errno_t.h b/libc/include/llvm-libc-types/errno_t.h
index a37b5dece2c35..e2c544ad19532 100644
--- a/libc/include/llvm-libc-types/errno_t.h
+++ b/libc/include/llvm-libc-types/errno_t.h
@@ -9,9 +9,12 @@
#ifndef LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
#define LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
-// LIBC_HAS_ANNEX_K is a necessary check guard here because errno_t is only
-// defined when Annex K is enabled. We use LIBC_HAS_ANNEX_K internally to
-// indicate whether Annex K is enabled or not.
+// LIBC_HAS_ANNEX_K is used to check whether C11 Annex K (the optional
+// “Bounds-checking interfaces”) is enabled in this libc implementation. Annex K
+// introduces additional types and functions, including `errno_t` (a typedef
+// used by the *_s functions). Since `errno_t` is *not defined* in the standard
+// library unless Annex K is enabled, we must guard any code that uses it with
+// LIBC_HAS_ANNEX_K.
#ifdef LIBC_HAS_ANNEX_K
typedef int errno_t;
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