git: 9e765fe77dab - main - devel/gdb: fix build with clang 16
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Date: Sun, 07 May 2023 18:39:39 UTC
The branch main has been updated by dim:
URL: https://cgit.FreeBSD.org/ports/commit/?id=9e765fe77dabf9e37b052510072b0f41a2ab3ae6
commit 9e765fe77dabf9e37b052510072b0f41a2ab3ae6
Author: Dimitry Andric <dim@FreeBSD.org>
AuthorDate: 2023-04-24 15:00:37 +0000
Commit: Dimitry Andric <dim@FreeBSD.org>
CommitDate: 2023-05-07 18:38:47 +0000
devel/gdb: fix build with clang 16
Clang 16 has a new error about integer values being outside the valid
range for enum types, which shows up when building gdb:
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/x86-fbsd-nat.c:20:
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/defs.h:65:
/wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/../gdbsupport/enum-flags.h:95:52: error: integer value -1 is outside the valid range of values [0, 15] for this enumeration type [-Wenum-constexpr-conversion]
integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
^
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/x86-bsd-nat.c:20:
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/defs.h:65:
/wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/../gdbsupport/enum-flags.h:95:52: error: integer value -1 is outside the valid range of values [0, 15] for this enumeration type [-Wenum-constexpr-conversion]
integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
^
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/x86-nat.c:20:
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/defs.h:65:
/wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/../gdbsupport/enum-flags.h:95:52: error: integer value -1 is outside the valid range of values [0, 15] for this enumeration type [-Wenum-constexpr-conversion]
integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
^
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/windows-tdep.c:18:
In file included from /wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/defs.h:65:
/wrkdirs/usr/ports/devel/gdb/work-py39/gdb-13.1/gdb/../gdbsupport/enum-flags.h:95:52: error: integer value -1 is outside the valid range of values [0, 15] for this enumeration type [-Wenum-constexpr-conversion]
integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
^
Upstream already noticed this, and committed
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=ae61525fcf4 as
a workaround, so add this as an additional patch, until gdb 13.2 is
released.
PR: 271045
Approved by: maintainer timeout (2 weeks)
MFH: 2023Q2
---
devel/gdb/Makefile | 3 +-
devel/gdb/files/commit-ae61525fcf4 | 128 +++++++++++++++++++++++++++++++++++++
2 files changed, 130 insertions(+), 1 deletion(-)
diff --git a/devel/gdb/Makefile b/devel/gdb/Makefile
index d11470e63b41..d0158a6c6b56 100644
--- a/devel/gdb/Makefile
+++ b/devel/gdb/Makefile
@@ -1,6 +1,6 @@
PORTNAME= gdb
DISTVERSION= 13.1
-PORTREVISION= 1
+PORTREVISION= 2
CATEGORIES= devel
MASTER_SITES= GNU
@@ -36,6 +36,7 @@ CFLAGS+= -DRL_NO_COMPAT
EXCLUDE= dejagnu expect sim texinfo intl
EXTRACT_AFTER_ARGS= ${EXCLUDE:S/^/--exclude /}
EXTRA_PATCHES= ${FILESDIR}/commit-a980a7d24b9
+EXTRA_PATCHES+= ${FILESDIR}/commit-ae61525fcf4
VER= ${DISTVERSION:S/.//g}
PLIST_SUB= VER=${VER}
diff --git a/devel/gdb/files/commit-ae61525fcf4 b/devel/gdb/files/commit-ae61525fcf4
new file mode 100644
index 000000000000..202f695b654c
--- /dev/null
+++ b/devel/gdb/files/commit-ae61525fcf4
@@ -0,0 +1,128 @@
+commit ae61525fcf456ab395d55c45492a106d1275873a
+Author: Simon Marchi <simon.marchi@efficios.com>
+Date: 2023-02-23 12:35:40 -0500
+
+ gdbsupport: ignore -Wenum-constexpr-conversion in enum-flags.h
+
+ When building with clang 16, we get:
+
+ CXX gdb.o
+ In file included from /home/smarchi/src/binutils-gdb/gdb/gdb.c:19:
+ In file included from /home/smarchi/src/binutils-gdb/gdb/defs.h:65:
+ /home/smarchi/src/binutils-gdb/gdb/../gdbsupport/enum-flags.h:95:52: error: integer value -1 is outside the valid range of values [0, 15] for this enumeration type [-Wenum-constexpr-conversion]
+ integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
+ ^
+
+ The error message does not make it clear in the context of which enum
+ flag this fails (i.e. what is T in this context), but it doesn't really
+ matter, we have similar warning/errors for many of them, if we let the
+ build go through.
+
+ clang is right that the value -1 is invalid for the enum type we cast -1
+ to. However, we do need this expression in order to select an integer
+ type with the appropriate signedness. That is, with the same signedness
+ as the underlying type of the enum.
+
+ I first wondered if that was really needed, if we couldn't use
+ std::underlying_type for that. It turns out that the comment just above
+ says:
+
+ /* Note that std::underlying_type<enum_type> is not what we want here,
+ since that returns unsigned int even when the enum decays to signed
+ int. */
+
+ I was surprised, because std::is_signed<std::underlying_type<enum_type>>
+ returns the right thing. So I tried replacing all this with
+ std::underlying_type, see if that would work. Doing so causes some
+ build failures in unittests/enum-flags-selftests.c:
+
+ CXX unittests/enum-flags-selftests.o
+ /home/smarchi/src/binutils-gdb/gdb/unittests/enum-flags-selftests.c:254:1: error: static assertion failed due to requirement 'gdb::is_same<selftests::enum_flags_tests::check_valid_expr254::archetype<enum_flags<s
+ elftests::enum_flags_tests::RE>, selftests::enum_flags_tests::RE, enum_flags<selftests::enum_flags_tests::RE2>, selftests::enum_flags_tests::RE2, enum_flags<selftests::enum_flags_tests::URE>, selftests::enum_fla
+ gs_tests::URE, int>, selftests::enum_flags_tests::check_valid_expr254::archetype<enum_flags<selftests::enum_flags_tests::RE>, selftests::enum_flags_tests::RE, enum_flags<selftests::enum_flags_tests::RE2>, selfte
+ sts::enum_flags_tests::RE2, enum_flags<selftests::enum_flags_tests::URE>, selftests::enum_flags_tests::URE, unsigned int>>::value == true':
+ CHECK_VALID (true, int, true ? EF () : EF2 ())
+ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ /home/smarchi/src/binutils-gdb/gdb/unittests/enum-flags-selftests.c:91:3: note: expanded from macro 'CHECK_VALID'
+ CHECK_VALID_EXPR_6 (EF, RE, EF2, RE2, UEF, URE, VALID, EXPR_TYPE, EXPR)
+ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ /home/smarchi/src/binutils-gdb/gdb/../gdbsupport/valid-expr.h:105:3: note: expanded from macro 'CHECK_VALID_EXPR_6'
+ CHECK_VALID_EXPR_INT (ESC_PARENS (typename T1, typename T2, \
+ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ /home/smarchi/src/binutils-gdb/gdb/../gdbsupport/valid-expr.h:66:3: note: expanded from macro 'CHECK_VALID_EXPR_INT'
+ static_assert (gdb::is_detected_exact<archetype<TYPES, EXPR_TYPE>, \
+ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+ This is a bit hard to decode, but basically enumerations have the
+ following funny property that they decay into a signed int, even if
+ their implicit underlying type is unsigned. This code:
+
+ enum A {};
+ enum B {};
+
+ int main() {
+ std::cout << std::is_signed<std::underlying_type<A>::type>::value
+ << std::endl;
+ std::cout << std::is_signed<std::underlying_type<B>::type>::value
+ << std::endl;
+ auto result = true ? A() : B();
+ std::cout << std::is_signed<decltype(result)>::value << std::endl;
+ }
+
+ produces:
+
+ 0
+ 0
+ 1
+
+ So, the "CHECK_VALID" above checks that this property works for enum flags the
+ same way as it would if you were using their underlying enum types. And
+ somehow, changing integer_for_size to use std::underlying_type breaks that.
+
+ Since the current code does what we want, and I don't see any way of doing it
+ differently, ignore -Wenum-constexpr-conversion around it.
+
+ Change-Id: Ibc82ae7bbdb812102ae3f1dd099fc859dc6f3cc2
+
+diff --git gdbsupport/enum-flags.h gdbsupport/enum-flags.h
+index 700037f6126..41ac7838f06 100644
+--- gdbsupport/enum-flags.h
++++ gdbsupport/enum-flags.h
+@@ -91,9 +91,12 @@ template<> struct integer_for_size<8, 1> { typedef int64_t type; };
+ template<typename T>
+ struct enum_underlying_type
+ {
++ DIAGNOSTIC_PUSH
++ DIAGNOSTIC_IGNORE_ENUM_CONSTEXPR_CONVERSION
+ typedef typename
+ integer_for_size<sizeof (T), static_cast<bool>(T (-1) < T (0))>::type
+ type;
++ DIAGNOSTIC_POP
+ };
+
+ namespace enum_flags_detail
+diff --git include/diagnostics.h include/diagnostics.h
+index d3ff27bc008..41e6db65391 100644
+--- include/diagnostics.h
++++ include/diagnostics.h
+@@ -76,6 +76,11 @@
+ # define DIAGNOSTIC_ERROR_SWITCH \
+ DIAGNOSTIC_ERROR ("-Wswitch")
+
++# if __has_warning ("-Wenum-constexpr-conversion")
++# define DIAGNOSTIC_IGNORE_ENUM_CONSTEXPR_CONVERSION \
++ DIAGNOSTIC_IGNORE ("-Wenum-constexpr-conversion")
++# endif
++
+ #elif defined (__GNUC__) /* GCC */
+
+ # define DIAGNOSTIC_IGNORE_DEPRECATED_DECLARATIONS \
+@@ -155,4 +160,8 @@
+ # define DIAGNOSTIC_ERROR_SWITCH
+ #endif
+
++#ifndef DIAGNOSTIC_IGNORE_ENUM_CONSTEXPR_CONVERSION
++# define DIAGNOSTIC_IGNORE_ENUM_CONSTEXPR_CONVERSION
++#endif
++
+ #endif /* DIAGNOSTICS_H */