[PATCH v2] lib/posixtm.c: Fixe build error with clang-18

[PATCH v2] lib/posixtm.c: Fixe build error with clang-18

[Khem Raj]

Clang-18 detects this and flags it as error

x86_64-yoe-linux-clang -target x86_64-yoe-linux  -m64 -march=core2 -mtune=core2 -msse3 -mfpmath=sse -mlittle-endian --dyld-prefix=/usr -Qunused-arguments -fstack-protector-strong  -O2 -D_FORTIFY_SOURCE=2 -Wformat -Wformat-security -Werror=format-security --sysroot=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/recipe-sysroot  -I. -I../coreutils-9.4 -I./lib  -Ilib -I../coreutils-9.4/lib -Isrc -I../coreutils-9.4/src    -Wno-cast-qual -Wno-conversion -Wno-float-equal -Wno-sign-compare -Wno-undef -Wno-unused-function -Wno-unused-parameter -Wno-float-conversion -Wimplicit-fallthrough -Wno-pedantic -Wno-sign-conversion -Wno-type-limits -O2 -pipe -g -feliminate-unused-debug-types   -fmacro-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/coreutils-9.4=/usr/src/debug/coreutils/9.4  -fdebug-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/coreutils-9.4=/usr/src/debug/coreutils/9.4  -fmacro-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/build=/usr/src/debug/coreutils/9.4  -fdebug-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/build=/usr/src/debug/coreutils/9.4  -fdebug-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/recipe-sysroot=  -fmacro-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/recipe-sysroot=  -fdebug-prefix-map=/mnt/b/yoe/master/build/tmp/work/core2-64-yoe-linux/coreutils/9.4/recipe-sysroot-native=  -c -o lib/libcoreutils_a-posixtm.o `test -f 'lib/posixtm.c'

lib/posixtm.c:194:15: error: operand argument to checked integer operation must be an integer type other than plain 'char', 'bool', bit-precise, or an enumeration ('bool' invalid)
  194 |           if (ckd_add (&t, t, leapsec))
      |               ^~~~~~~~~~~~~~~~~~~~~~~~
usr/lib/clang/18/include/stdckdint.h:37:54: note: expanded from macro 'ckd_add'
   37 | #define ckd_add(R, A, B) __builtin_add_overflow((A), (B), (R))
      |                                                      ^~~
1 error generated.

* lib/posixtm.c (posixtime): Fix operand argument to checked
integer operation.

Signed-off-by: Khem Raj <raj.khem@gmail.com>
---
 ChangeLog     | 5 +++++
 lib/posixtm.c | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index e42d2c31ab..daca27a917 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2024-01-15  Khem Raj  <raj.khem@gmail.com>
+
+	* lib/posixtm.c (posixtime): Fix operand argument to checked
+	integer operation.
+
 2024-01-07  Jim Meyering  <meyering@meta.com>
 
 	update-copyright: handle more cases
diff --git a/lib/posixtm.c b/lib/posixtm.c
index ef9f55f873..23397a6672 100644
--- a/lib/posixtm.c
+++ b/lib/posixtm.c
@@ -159,7 +159,7 @@ bool
 posixtime (time_t *p, const char *s, unsigned int syntax_bits)
 {
   struct tm tm0;
-  bool leapsec = false;
+  int leapsec = 0;
 
   if (! posix_time_parse (&tm0, s, syntax_bits))
     return false;
-- 
2.43.0

Re: [PATCH v2] lib/posixtm.c: Fixe build error with clang-18

[Paul Eggert]

[-- Attachment #1: Type: text/plain, Size: 113 bytes --]

Thanks, I installed the attached simpler (1-byte!) fix. Please give it a 
try, as I lack easy access to clang 18.

[-- Attachment #2: 0001-posixtm-pacify-clang-18.patch --]
[-- Type: text/x-patch, Size: 1795 bytes --]

From 67c298c36f69b6906840b7584be06b7b5f33f829 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Tue, 16 Jan 2024 17:21:08 -0800
Subject: [PATCH] posixtm: pacify clang 18
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Problem reported by Khem Raj in:
https://lists.gnu.org/r/bug-gnulib/2024-01/msg00045.html
* lib/posixtm.c (posixtime): Pacify clang 18 by converting bool to int.
Arguably this is a bug in draft C2x, since the non-pointer args to
ckd_add should promote just like any other expressions do;
but that’s not clang’s fault.
---
 ChangeLog     | 10 ++++++++++
 lib/posixtm.c |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index e42d2c31ab..8551538ee8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2024-01-16  Paul Eggert  <eggert@cs.ucla.edu>
+
+	posixtm: pacify clang 18
+	Problem reported by Khem Raj in:
+	https://lists.gnu.org/r/bug-gnulib/2024-01/msg00045.html
+	* lib/posixtm.c (posixtime): Pacify clang 18 by converting bool to int.
+	Arguably this is a bug in draft C2x, since the non-pointer args to
+	ckd_add should promote just like any other expressions do;
+	but that’s not clang’s fault.
+
 2024-01-07  Jim Meyering  <meyering@meta.com>
 
 	update-copyright: handle more cases
diff --git a/lib/posixtm.c b/lib/posixtm.c
index ef9f55f873..a072c7cad0 100644
--- a/lib/posixtm.c
+++ b/lib/posixtm.c
@@ -191,7 +191,7 @@ posixtime (time_t *p, const char *s, unsigned int syntax_bits)
              | (tm0.tm_min ^ tm1.tm_min)
              | (tm0.tm_sec ^ tm1.tm_sec)))
         {
-          if (ckd_add (&t, t, leapsec))
+          if (ckd_add (&t, t, +leapsec))
             return false;
           *p = t;
           return true;
-- 
2.43.0

Re: [PATCH v2] lib/posixtm.c: Fixe build error with clang-18

[Khem Raj]

On Tue, Jan 16, 2024 at 5:25 PM Paul Eggert <eggert@cs.ucla.edu> wrote:
>
> Thanks, I installed the attached simpler (1-byte!) fix. Please give it a
> try, as I lack easy access to clang 18.

Ah cool!. This works for me too.