toolchain: binutils: fix compilation with GCC15

GCC15 has switched the C language default from GNU17 to GNU23[1] and this
causes builds to fail with:
In file included from mips-opc.c:29:
mips-opc.c: In function 'decode_mips_operand':
mips-formats.h:86:7: error: expected identifier or '(' before 'static_assert'
   86 |       static_assert[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
      |       ^~~~~~~~~~~~~
mips-opc.c:214:15: note: in expansion of macro 'MAPPED_REG'
  214 |     case 'z': MAPPED_REG (0, 0, GP, reg_0_map);
      |               ^~~~~~~~~~

So, backport upstream fix for this[2] to fix compilation with GCC15.
Patch for 2.40 was manually refreshed as part of the S390 code does not
exist in 2.40 as it was added after it.

[1] https://gcc.gnu.org/gcc-15/porting_to.html#c23
[2] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=8ebe62f3f0d27806b1bf69f301f5e188b4acd2b4

Fixes: #18678
Link: https://github.com/openwrt/openwrt/pull/18681
Signed-off-by: Robert Marko <robimarko@gmail.com>
(cherry picked from commit d3216173abfc47917807423fc7578406ea29db5b)
Link: https://github.com/openwrt/openwrt/pull/19065
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

diff --git a/toolchain/binutils/patches/2.40/050-PR-32372-opcodes-fix-std-gnu23-compatibility-wrt-static_asser.patch b/toolchain/binutils/patches/2.40/050-PR-32372-opcodes-fix-std-gnu23-compatibility-wrt-static_asser.patch
new file mode 100644 (file)
index 0000000..3364e9a
--- /dev/null
+++ b/toolchain/binutils/patches/2.40/050-PR-32372-opcodes-fix-std-gnu23-compatibility-wrt-static_asser.patch
@@ -0,0 +1,66 @@
+From 8ebe62f3f0d27806b1bf69f301f5e188b4acd2b4 Mon Sep 17 00:00:00 2001
+From: Sam James <sam@gentoo.org>
+Date: Sat, 16 Nov 2024 05:03:52 +0000
+Subject: [PATCH] opcodes: fix -std=gnu23 compatibility wrt static_assert
+
+static_assert is declared in C23 so we can't reuse that identifier:
+* Define our own static_assert conditionally;
+
+* Rename "static assert" hacks to _N as we do already in some places
+  to avoid a conflict.
+
+ChangeLog:
+       PR ld/32372
+
+        * i386-gen.c (static_assert): Define conditionally.
+        * mips-formats.h (MAPPED_INT): Rename identifier.
+        (MAPPED_REG): Rename identifier.
+        (OPTIONAL_MAPPED_REG): Rename identifier.
+        * s390-opc.c (static_assert): Define conditionally.
+---
+ opcodes/i386-gen.c     | 2 ++
+ opcodes/mips-formats.h | 6 +++---
+ opcodes/s390-opc.c     | 2 ++
+ 3 files changed, 7 insertions(+), 3 deletions(-)
+
+--- a/opcodes/i386-gen.c
++++ b/opcodes/i386-gen.c
+@@ -33,7 +33,9 @@
+ 
+ /* Build-time checks are preferrable over runtime ones.  Use this construct
+    in preference where possible.  */
++#ifndef static_assert
+ #define static_assert(e) ((void)sizeof (struct { int _:1 - 2 * !(e); }))
++#endif
+ 
+ static const char *program_name = NULL;
+ static int debug = 0;
+--- a/opcodes/mips-formats.h
++++ b/opcodes/mips-formats.h
+@@ -49,7 +49,7 @@
+ #define MAPPED_INT(SIZE, LSB, MAP, PRINT_HEX) \
+   { \
+     typedef char ATTRIBUTE_UNUSED \
+-      static_assert[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
++      static_assert_3[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
+     static const struct mips_mapped_int_operand op = { \
+       { OP_MAPPED_INT, SIZE, LSB }, MAP, PRINT_HEX \
+     }; \
+@@ -83,7 +83,7 @@
+ #define MAPPED_REG(SIZE, LSB, BANK, MAP) \
+   { \
+     typedef char ATTRIBUTE_UNUSED \
+-      static_assert[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
++      static_assert_4[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
+     static const struct mips_reg_operand op = { \
+       { OP_REG, SIZE, LSB }, OP_REG_##BANK, MAP \
+     }; \
+@@ -93,7 +93,7 @@
+ #define OPTIONAL_MAPPED_REG(SIZE, LSB, BANK, MAP) \
+   { \
+     typedef char ATTRIBUTE_UNUSED \
+-      static_assert[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
++      static_assert_5[(1 << (SIZE)) == ARRAY_SIZE (MAP)]; \
+     static const struct mips_reg_operand op = { \
+       { OP_OPTIONAL_REG, SIZE, LSB }, OP_REG_##BANK, MAP \
+     }; \