diff options
Diffstat (limited to 'meta-agl-bsp/meta-rcar-gen3/recipes-kernel/linux/files')
| -rw-r--r-- | meta-agl-bsp/meta-rcar-gen3/recipes-kernel/linux/files/0001-give-up-on-gcc-ilog2-constant-optimizations.patch | 127 |
1 files changed, 0 insertions, 127 deletions
diff --git a/meta-agl-bsp/meta-rcar-gen3/recipes-kernel/linux/files/0001-give-up-on-gcc-ilog2-constant-optimizations.patch b/meta-agl-bsp/meta-rcar-gen3/recipes-kernel/linux/files/0001-give-up-on-gcc-ilog2-constant-optimizations.patch deleted file mode 100644 index 67b455da6..000000000 --- a/meta-agl-bsp/meta-rcar-gen3/recipes-kernel/linux/files/0001-give-up-on-gcc-ilog2-constant-optimizations.patch +++ /dev/null @@ -1,127 +0,0 @@ -From 474c90156c8dcc2fa815e6716cc9394d7930cb9c Mon Sep 17 00:00:00 2001 -From: Linus Torvalds <torvalds@linux-foundation.org> -Date: Thu, 2 Mar 2017 12:17:22 -0800 -Subject: [PATCH] give up on gcc ilog2() constant optimizations - -gcc-7 has an "optimization" pass that completely screws up, and -generates the code expansion for the (impossible) case of calling -ilog2() with a zero constant, even when the code gcc compiles does not -actually have a zero constant. - -And we try to generate a compile-time error for anybody doing ilog2() on -a constant where that doesn't make sense (be it zero or negative). So -now gcc7 will fail the build due to our sanity checking, because it -created that constant-zero case that didn't actually exist in the source -code. - -There's a whole long discussion on the kernel mailing about how to work -around this gcc bug. The gcc people themselevs have discussed their -"feature" in - - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72785 - -but it's all water under the bridge, because while it looked at one -point like it would be solved by the time gcc7 was released, that was -not to be. - -So now we have to deal with this compiler braindamage. - -And the only simple approach seems to be to just delete the code that -tries to warn about bad uses of ilog2(). - -So now "ilog2()" will just return 0 not just for the value 1, but for -any non-positive value too. - -It's not like I can recall anybody having ever actually tried to use -this function on any invalid value, but maybe the sanity check just -meant that such code never made it out in public. - -Reported-by: Laura Abbott <labbott@redhat.com> -Cc: John Stultz <john.stultz@linaro.org>, -Cc: Thomas Gleixner <tglx@linutronix.de> -Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> -Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> ---- - include/linux/log2.h | 13 ++----------- - tools/include/linux/log2.h | 13 ++----------- - 2 files changed, 4 insertions(+), 22 deletions(-) - -diff --git a/include/linux/log2.h b/include/linux/log2.h -index ef3d4f67118c..c373295f359f 100644 ---- a/include/linux/log2.h -+++ b/include/linux/log2.h -@@ -16,12 +16,6 @@ - #include <linux/bitops.h> - - /* -- * deal with unrepresentable constant logarithms -- */ --extern __attribute__((const, noreturn)) --int ____ilog2_NaN(void); -- --/* - * non-constant log of base 2 calculators - * - the arch may override these in asm/bitops.h if they can be implemented - * more efficiently than using fls() and fls64() -@@ -85,7 +79,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n) - #define ilog2(n) \ - ( \ - __builtin_constant_p(n) ? ( \ -- (n) < 1 ? ____ilog2_NaN() : \ -+ (n) < 2 ? 0 : \ - (n) & (1ULL << 63) ? 63 : \ - (n) & (1ULL << 62) ? 62 : \ - (n) & (1ULL << 61) ? 61 : \ -@@ -148,10 +142,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n) - (n) & (1ULL << 4) ? 4 : \ - (n) & (1ULL << 3) ? 3 : \ - (n) & (1ULL << 2) ? 2 : \ -- (n) & (1ULL << 1) ? 1 : \ -- (n) & (1ULL << 0) ? 0 : \ -- ____ilog2_NaN() \ -- ) : \ -+ 1 ) : \ - (sizeof(n) <= 4) ? \ - __ilog2_u32(n) : \ - __ilog2_u64(n) \ -diff --git a/tools/include/linux/log2.h b/tools/include/linux/log2.h -index 41446668ccce..d5677d39c1e4 100644 ---- a/tools/include/linux/log2.h -+++ b/tools/include/linux/log2.h -@@ -13,12 +13,6 @@ - #define _TOOLS_LINUX_LOG2_H - - /* -- * deal with unrepresentable constant logarithms -- */ --extern __attribute__((const, noreturn)) --int ____ilog2_NaN(void); -- --/* - * non-constant log of base 2 calculators - * - the arch may override these in asm/bitops.h if they can be implemented - * more efficiently than using fls() and fls64() -@@ -78,7 +72,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n) - #define ilog2(n) \ - ( \ - __builtin_constant_p(n) ? ( \ -- (n) < 1 ? ____ilog2_NaN() : \ -+ (n) < 2 ? 0 : \ - (n) & (1ULL << 63) ? 63 : \ - (n) & (1ULL << 62) ? 62 : \ - (n) & (1ULL << 61) ? 61 : \ -@@ -141,10 +135,7 @@ unsigned long __rounddown_pow_of_two(unsigned long n) - (n) & (1ULL << 4) ? 4 : \ - (n) & (1ULL << 3) ? 3 : \ - (n) & (1ULL << 2) ? 2 : \ -- (n) & (1ULL << 1) ? 1 : \ -- (n) & (1ULL << 0) ? 0 : \ -- ____ilog2_NaN() \ -- ) : \ -+ 1 ) : \ - (sizeof(n) <= 4) ? \ - __ilog2_u32(n) : \ - __ilog2_u64(n) \ --- -2.13.6 - |