Hi Bruno,
Bruno Haible <br...@clisp.org> writes:
> Also, I see that MSVC is not well covered by this default in stdbit.in.h:
>
> #else
> /* This platform is so old that it lacks typeof, so _Generic is likely
> missing or unreliable. The C23 standard seems to allow yielding B
> (which is always unsigned long long int), so do that. */
> # define _GL_STDBIT_TYPEOF_CAST(a, b) (b)
> #endif
>
> Can it be improved?
Good point.
I see that MSVC supports both typeof and __typeof__ since Visual Studio
17.9. The difference is 'typeof' requires compiling with the latest
language standard, but '__typeof__' can be used with any language
version [1].
I've applied the two attached patches to detect them in stdbit-h and
intprops using the _MSC_VER [2].
Collin
[1] https://learn.microsoft.com/en-us/cpp/c-language/typeof-c?view=msvc-170
[2]
https://learn.microsoft.com/en-us/cpp/overview/compiler-versions?view=msvc-170#version-macros
>From 1a9d52aadabd3862168da43926ab4518bd7ae02f Mon Sep 17 00:00:00 2001
From: Collin Funk <collin.fu...@gmail.com>
Date: Thu, 19 Dec 2024 17:53:48 -0800
Subject: [PATCH 1/2] stdbit-h: Detect MSVC __typeof__ support.
* lib/stdbit.in.h (_GL_STDBIT_TYPEOF_CAST): Use __typeof__ on Visual
Studio 2022 version 17.9 and later.
---
ChangeLog | 6 ++++++
lib/stdbit.in.h | 3 ++-
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/ChangeLog b/ChangeLog
index cf98e92c62..59fa232bd7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2024-12-19 Collin Funk <collin.fu...@gmail.com>
+
+ stdbit-h: Detect MSVC __typeof__ support.
+ * lib/stdbit.in.h (_GL_STDBIT_TYPEOF_CAST): Use __typeof__ on Visual
+ Studio 2022 version 17.9 and later.
+
2024-12-18 Pádraig Brady <p...@draigbrady.com>
crc-x86_64: fix build failure due to indentation
diff --git a/lib/stdbit.in.h b/lib/stdbit.in.h
index 20b9f4f466..91d237d7ad 100644
--- a/lib/stdbit.in.h
+++ b/lib/stdbit.in.h
@@ -77,7 +77,8 @@ _GL_INLINE_HEADER_BEGIN
#if ((defined __GNUC__ && 2 <= __GNUC__) \
|| (defined __clang_major__ && 4 <= __clang_major__) \
|| (defined __IBMC__ && 1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
- || (defined __SUNPRO_C && 0x5110 <= __SUNPRO_C && !__STDC__))
+ || (defined __SUNPRO_C && 0x5110 <= __SUNPRO_C && !__STDC__) \
+ || (defined _MSC_VER && 1939 <= _MSC_VER))
# define _GL_STDBIT_TYPEOF_CAST(a, b) ((__typeof__ (a)) (b))
#elif 202311 <= __STDC_VERSION__
# define _GL_STDBIT_TYPEOF_CAST(a, b) ((typeof (a)) (b))
--
2.47.1
>From 9e301775ffce832647850c1103008303e64688c9 Mon Sep 17 00:00:00 2001
From: Collin Funk <collin.fu...@gmail.com>
Date: Thu, 19 Dec 2024 17:59:57 -0800
Subject: [PATCH 2/2] intprops: Detect MSVC __typeof__ support.
* lib/intprops-internal.h (_GL_HAVE___TYPEOF__): Copy condition from
lib/stdbit.in.h.
---
ChangeLog | 4 ++++
lib/intprops-internal.h | 9 +++++----
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 59fa232bd7..4a453a39f6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
2024-12-19 Collin Funk <collin.fu...@gmail.com>
+ intprops: Detect MSVC __typeof__ support.
+ * lib/intprops-internal.h (_GL_HAVE___TYPEOF__): Copy condition from
+ lib/stdbit.in.h.
+
stdbit-h: Detect MSVC __typeof__ support.
* lib/stdbit.in.h (_GL_STDBIT_TYPEOF_CAST): Use __typeof__ on Visual
Studio 2022 version 17.9 and later.
diff --git a/lib/intprops-internal.h b/lib/intprops-internal.h
index c8cc0e2019..0b7e1f539a 100644
--- a/lib/intprops-internal.h
+++ b/lib/intprops-internal.h
@@ -77,10 +77,11 @@
/* Does the __typeof__ keyword work? This could be done by
'configure', but for now it's easier to do it by hand. */
-#if (2 <= __GNUC__ \
- || (4 <= __clang_major__) \
- || (1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
- || (0x5110 <= __SUNPRO_C && !__STDC__))
+#if ((defined __GNUC__ && 2 <= __GNUC__) \
+ || (defined __clang_major__ && 4 <= __clang_major__) \
+ || (defined __IBMC__ && 1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
+ || (defined __SUNPRO_C && 0x5110 <= __SUNPRO_C && !__STDC__) \
+ || (defined _MSC_VER && 1939 <= _MSC_VER))
# define _GL_HAVE___TYPEOF__ 1
#else
# define _GL_HAVE___TYPEOF__ 0
--
2.47.1
