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-rw-r--r--include/linux/compiler-gcc.h154
1 files changed, 154 insertions, 0 deletions
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
new file mode 100644
index 000000000..f55a37efd
--- /dev/null
+++ b/include/linux/compiler-gcc.h
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_COMPILER_TYPES_H
+#error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead."
+#endif
+
+/*
+ * Common definitions for all gcc versions go here.
+ */
+#define GCC_VERSION (__GNUC__ * 10000 \
+ + __GNUC_MINOR__ * 100 \
+ + __GNUC_PATCHLEVEL__)
+
+/*
+ * This macro obfuscates arithmetic on a variable address so that gcc
+ * shouldn't recognize the original var, and make assumptions about it.
+ *
+ * This is needed because the C standard makes it undefined to do
+ * pointer arithmetic on "objects" outside their boundaries and the
+ * gcc optimizers assume this is the case. In particular they
+ * assume such arithmetic does not wrap.
+ *
+ * A miscompilation has been observed because of this on PPC.
+ * To work around it we hide the relationship of the pointer and the object
+ * using this macro.
+ *
+ * Versions of the ppc64 compiler before 4.1 had a bug where use of
+ * RELOC_HIDE could trash r30. The bug can be worked around by changing
+ * the inline assembly constraint from =g to =r, in this particular
+ * case either is valid.
+ */
+#define RELOC_HIDE(ptr, off) \
+({ \
+ unsigned long __ptr; \
+ __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \
+ (typeof(ptr)) (__ptr + (off)); \
+})
+
+#ifdef CONFIG_RETPOLINE
+#define __noretpoline __attribute__((__indirect_branch__("keep")))
+#endif
+
+#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
+
+#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)
+#define __latent_entropy __attribute__((latent_entropy))
+#endif
+
+/*
+ * calling noreturn functions, __builtin_unreachable() and __builtin_trap()
+ * confuse the stack allocation in gcc, leading to overly large stack
+ * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
+ *
+ * Adding an empty inline assembly before it works around the problem
+ */
+#define barrier_before_unreachable() asm volatile("")
+
+/*
+ * Mark a position in code as unreachable. This can be used to
+ * suppress control flow warnings after asm blocks that transfer
+ * control elsewhere.
+ */
+#define unreachable() \
+ do { \
+ annotate_unreachable(); \
+ barrier_before_unreachable(); \
+ __builtin_unreachable(); \
+ } while (0)
+
+#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP)
+#define __HAVE_BUILTIN_BSWAP32__
+#define __HAVE_BUILTIN_BSWAP64__
+#define __HAVE_BUILTIN_BSWAP16__
+#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
+
+#if GCC_VERSION >= 70000
+#define KASAN_ABI_VERSION 5
+#else
+#define KASAN_ABI_VERSION 4
+#endif
+
+#ifdef CONFIG_SHADOW_CALL_STACK
+#define __noscs __attribute__((__no_sanitize__("shadow-call-stack")))
+#endif
+
+#if __has_attribute(__no_sanitize_address__)
+#define __no_sanitize_address __attribute__((no_sanitize_address))
+#else
+#define __no_sanitize_address
+#endif
+
+#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)
+#define __no_sanitize_thread __attribute__((no_sanitize_thread))
+#else
+#define __no_sanitize_thread
+#endif
+
+#if __has_attribute(__no_sanitize_undefined__)
+#define __no_sanitize_undefined __attribute__((no_sanitize_undefined))
+#else
+#define __no_sanitize_undefined
+#endif
+
+#if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__)
+#define __no_sanitize_coverage __attribute__((no_sanitize_coverage))
+#else
+#define __no_sanitize_coverage
+#endif
+
+/*
+ * Treat __SANITIZE_HWADDRESS__ the same as __SANITIZE_ADDRESS__ in the kernel,
+ * matching the defines used by Clang.
+ */
+#ifdef __SANITIZE_HWADDRESS__
+#define __SANITIZE_ADDRESS__
+#endif
+
+/*
+ * GCC does not support KMSAN.
+ */
+#define __no_sanitize_memory
+#define __no_kmsan_checks
+
+/*
+ * Turn individual warnings and errors on and off locally, depending
+ * on version.
+ */
+#define __diag_GCC(version, severity, s) \
+ __diag_GCC_ ## version(__diag_GCC_ ## severity s)
+
+/* Severity used in pragma directives */
+#define __diag_GCC_ignore ignored
+#define __diag_GCC_warn warning
+#define __diag_GCC_error error
+
+#define __diag_str1(s) #s
+#define __diag_str(s) __diag_str1(s)
+#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))
+
+#if GCC_VERSION >= 80000
+#define __diag_GCC_8(s) __diag(s)
+#else
+#define __diag_GCC_8(s)
+#endif
+
+#define __diag_ignore_all(option, comment) \
+ __diag_GCC(8, ignore, option)
+
+/*
+ * Prior to 9.1, -Wno-alloc-size-larger-than (and therefore the "alloc_size"
+ * attribute) do not work, and must be disabled.
+ */
+#if GCC_VERSION < 90100
+#undef __alloc_size__
+#endif