I tried to build coreutils using recent gcc, built from git, so it
calls itself "gcc version 9.0.0 20180616 (experimental) (GCC)".
There were three gnulib-related build failures. These were errors
solely because I also configured with --enable-gcc-warnings.
With these three changes to gnulib files, the build succeeded:
>From 593c1703712ec68b1e59bd7f1764d990e030ec69 Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyer...@fb.com>
Date: Sun, 24 Jun 2018 11:31:50 -0700
Subject: [PATCH 1/3] manywarnings: accommodate GCC 9.0-pre: remove -Wchkp and
-Wabi
* build-aux/gcc-warning.spec: Add them here, each with an explanation.
* m4/manywarnings.m4: Remove them.
Otherwise, building coreutils, I would see this:
cc1: error: deprecated command line option '-Wchkp' [-Werror]
cc1: error: -Wabi won't warn about anything [-Werror=abi]
cc1: note: -Wabi warns about differences from the most up-to-date ABI,\
which is also used by default
cc1: note: use e.g. -Wabi=11 to warn about changes from GCC 7
---
ChangeLog | 12 ++++++++++++
build-aux/gcc-warning.spec | 2 ++
m4/manywarnings.m4 | 2 --
3 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 110487657..546da3218 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2018-06-24 Jim Meyering <meyer...@fb.com>
+
+ manywarnings: accommodate GCC 9.0-pre: remove -Wchkp and -Wabi
+ * build-aux/gcc-warning.spec: Add them here, each with an explanation.
+ * m4/manywarnings.m4: Remove them.
+ Otherwise, building coreutils, I would see this:
+ cc1: error: deprecated command line option '-Wchkp' [-Werror]
+ cc1: error: -Wabi won't warn about anything [-Werror=abi]
+ cc1: note: -Wabi warns about differences from the most up-to-date ABI,\
+ which is also used by default
+ cc1: note: use e.g. -Wabi=11 to warn about changes from GCC 7
+
2018-06-03 Paul Eggert <egg...@cs.ucla.edu>
Port crypto/af_alg to GCC 4.8.4
diff --git a/build-aux/gcc-warning.spec b/build-aux/gcc-warning.spec
index 2ffdb2ba4..e2625ea9d 100644
--- a/build-aux/gcc-warning.spec
+++ b/build-aux/gcc-warning.spec
@@ -3,6 +3,7 @@
--extra-warnings alias for -Wextra
-Wabi-tag c++
-Wabi= c++
+-Wabi this is now a no-op
-Waggregate-return obsolescent
-Waliasing fortran
-Walign-commons fortran
@@ -30,6 +31,7 @@
-Wcatch-value c++
-Wcatch-value=<0,3> c++
-Wcharacter-truncation fortran
+-Wchkp deprecated
-Wclass-memaccess c++
-Wcompare-reals fortran
-Wconditionally-supported c++ and objc++
diff --git a/m4/manywarnings.m4 b/m4/manywarnings.m4
index 60c0e4051..350c1355d 100644
--- a/m4/manywarnings.m4
+++ b/m4/manywarnings.m4
@@ -113,7 +113,6 @@ m4_defun([gl_MANYWARN_ALL_GCC(C)],
gl_manywarn_set=
for gl_manywarn_item in -fno-common \
-W \
- -Wabi \
-Waddress \
-Waggressive-loop-optimizations \
-Wall \
@@ -128,7 +127,6 @@ m4_defun([gl_MANYWARN_ALL_GCC(C)],
-Wcast-align=strict \
-Wcast-function-type \
-Wchar-subscripts \
- -Wchkp \
-Wclobbered \
-Wcomment \
-Wcomments \
--
2.18.0.rc2
>From 03fc6e299b3bdb255ee5f70fbec31feaf69717e8 Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyer...@fb.com>
Date: Sun, 24 Jun 2018 11:51:48 -0700
Subject: [PATCH 2/3] canon-host.c: avoid spurious GCC 9 warning
* lib/canon-host.c: Suppress GCC9's -Wsuggest-attribute=malloc.
---
ChangeLog | 3 +++
lib/canon-host.c | 6 ++++++
2 files changed, 9 insertions(+)
diff --git a/ChangeLog b/ChangeLog
index 546da3218..d325d42ed 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
2018-06-24 Jim Meyering <meyer...@fb.com>
+ canon-host.c: avoid spurious GCC 9 warning
+ * lib/canon-host.c: Suppress GCC9's -Wsuggest-attribute=malloc.
+
manywarnings: accommodate GCC 9.0-pre: remove -Wchkp and -Wabi
* build-aux/gcc-warning.spec: Add them here, each with an explanation.
* m4/manywarnings.m4: Remove them.
diff --git a/lib/canon-host.c b/lib/canon-host.c
index f2a16a758..64afe1a0a 100644
--- a/lib/canon-host.c
+++ b/lib/canon-host.c
@@ -17,6 +17,12 @@
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
+/* Without this pragma, gcc version 9.0.0 20180616 suggests that
+ the canon_* functions might be candidateifor attribute 'malloc' */
+#if 9 <= __GNUC__
+# pragma GCC diagnostic ignored "-Wsuggest-attribute=malloc"
+#endif
+
#include <config.h>
#include "canon-host.h"
--
2.18.0.rc2
>From 131b984c708d174366d5e6d224c5164a7225ee7c Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyer...@fb.com>
Date: Sun, 24 Jun 2018 15:58:09 -0700
Subject: [PATCH 3/3] parse-datetime.y: avoid spurious GCC 9 warning
* lib/parse-datetime.y (parse_datetime2): Save RELATIVE_TIME_0 into
a function local prior to the first "goto fail". The prior use would
evoke this:
parse-datetime.y: In function 'parse_datetime2':
parse-datetime.y:1791:19: error: jump skips variable initialization \
[-Werror=jump-misses-init]
parse-datetime.y:2385:2: note: label 'fail' defined here
parse-datetime.y:188:43: note: '({anonymous})' declared here
parse-datetime.y:1841:12: note: in expansion of macro 'RELATIVE_TIME_0'
---
ChangeLog | 11 +++++++++++
lib/parse-datetime.y | 7 ++++++-
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/ChangeLog b/ChangeLog
index d325d42ed..9d1a3e337 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,16 @@
2018-06-24 Jim Meyering <meyer...@fb.com>
+ parse-datetime.y: avoid spurious GCC 9 warning
+ * lib/parse-datetime.y (parse_datetime2): Save RELATIVE_TIME_0 into
+ a function local prior to the first "goto fail". The prior use would
+ evoke this:
+ parse-datetime.y: In function 'parse_datetime2':
+ parse-datetime.y:1791:19: error: jump skips variable initialization \
+ [-Werror=jump-misses-init]
+ parse-datetime.y:2385:2: note: label 'fail' defined here
+ parse-datetime.y:188:43: note: '({anonymous})' declared here
+ parse-datetime.y:1841:12: note: in expansion of macro 'RELATIVE_TIME_0'
+
canon-host.c: avoid spurious GCC 9 warning
* lib/canon-host.c: Suppress GCC9's -Wsuggest-attribute=malloc.
diff --git a/lib/parse-datetime.y b/lib/parse-datetime.y
index f14bb31dc..3d8666a4d 100644
--- a/lib/parse-datetime.y
+++ b/lib/parse-datetime.y
@@ -1766,6 +1766,11 @@ parse_datetime2 (struct timespec *result, char const *p,
timezone_t tz = tzdefault;
+ /* Store a local copy prior to first "goto". Without this, a prior use
+ below of RELATIVE_TIME_0 on the RHS might translate to an assignment-
+ to-temporary, which would trigger a -Wjump-misses-init warning. */
+ static const relative_time rel_time_0 = RELATIVE_TIME_0;
+
if (strncmp (p, "TZ=\"", 4) == 0)
{
char const *tzbase = p + 4;
@@ -1838,7 +1843,7 @@ parse_datetime2 (struct timespec *result, char const *p,
tm.tm_isdst = tmp.tm_isdst;
pc.meridian = MER24;
- pc.rel = RELATIVE_TIME_0;
+ pc.rel = rel_time_0;
pc.timespec_seen = false;
pc.rels_seen = false;
pc.dates_seen = 0;
--
2.18.0
