Remove patch for GCC VTA

It's been years and gcc has changed a lot.

Signed-off-by: Laura Abbott <labbott@redhat.com>

1 files changed, 0 insertions, 94 deletions

diff --git a/Kbuild-Add-an-option-to-enable-GCC-VTA.patch b/Kbuild-Add-an-option-to-enable-GCC-VTA.patch
deleted file mode 100644
index 6bbb0efdf..000000000
--- a/Kbuild-Add-an-option-to-enable-GCC-VTA.patch
+++ /dev/null
@@ -1,94 +0,0 @@
-From a446d2f94ce540689c7a46bf457d92409e9c4d7e Mon Sep 17 00:00:00 2001
-From: Josh Stone <jistone@redhat.com>
-Date: Fri, 21 Nov 2014 10:40:00 -0800
-Subject: [PATCH] Kbuild: Add an option to enable GCC VTA
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-Due to recent codegen issues, gcc -fvar-tracking-assignments was
-unconditionally disabled in commit 2062afb4f804a ("Fix gcc-4.9.0
-miscompilation of load_balance() in scheduler").  However, this reduces
-the debuginfo coverage for variable locations, especially in inline
-functions.  VTA is certainly not perfect either in those cases, but it
-is much better than without.  With compiler versions that have fixed the
-codegen bugs, we would prefer to have the better details for SystemTap,
-and surely other debuginfo consumers like perf will benefit as well.
-
-This patch simply makes CONFIG_DEBUG_INFO_VTA an option.  I considered
-Frank and Linus's discussion of a cc-option-like -fcompare-debug test,
-but I'm convinced that a narrow test of an arch-specific codegen issue
-is not really useful.  GCC has their own regression tests for this, so
-I'd suggest GCC_COMPARE_DEBUG=-fvar-tracking-assignments-toggle is more
-useful for kernel developers to test confidence.
-
-In fact, I ran into a couple more issues when testing for this patch[1],
-although neither of those had any codegen impact.
- [1] https://bugzilla.redhat.com/show_bug.cgi?id=1140872
-
-With gcc-4.9.2-1.fc22, I can now build v3.18-rc5 with Fedora's i686 and
-x86_64 configs, and this is completely clean with GCC_COMPARE_DEBUG.
-
-Cc: Frank Ch. Eigler <fche@redhat.com>
-Cc: Jakub Jelinek <jakub@redhat.com>
-Cc: Josh Boyer <jwboyer@fedoraproject.org>
-Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-Cc: Linus Torvalds <torvalds@linux-foundation.org>
-Cc: Andrew Morton <akpm@linux-foundation.org>
-Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
-Cc: Michel Dänzer <michel@daenzer.net>
-Signed-off-by: Josh Stone <jistone@redhat.com>
-Signed-off-by: Jeremy Cline <jcline@redhat.com>
----
- Makefile          |  4 ++++
- lib/Kconfig.debug | 18 +++++++++++++++++-
- 2 files changed, 21 insertions(+), 1 deletion(-)
-
-diff --git a/Makefile b/Makefile
-index 9ef547fc7ffe..5777d902f8f3 100644
---- a/Makefile
-+++ b/Makefile
-@@ -735,7 +735,11 @@ KBUILD_CFLAGS	+= -fomit-frame-pointer
- KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
- endif
- 
-+ifdef CONFIG_DEBUG_INFO_VTA
-+DEBUG_CFLAGS	+= $(call cc-option, -fvar-tracking-assignments)
-+else
- DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
-+endif
- 
- ifdef CONFIG_DEBUG_INFO
- ifdef CONFIG_DEBUG_INFO_SPLIT
-diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
-index 0d9e81779e37..424206212931 100644
---- a/lib/Kconfig.debug
-+++ b/lib/Kconfig.debug
-@@ -217,7 +217,23 @@ config DEBUG_INFO_DWARF4
- 	  Generate dwarf4 debug info. This requires recent versions
- 	  of gcc and gdb. It makes the debug information larger.
- 	  But it significantly improves the success of resolving
--	  variables in gdb on optimized code.
-+	  variables in gdb on optimized code.  The gcc docs also
-+	  recommend enabling -fvar-tracking-assignments for maximum
-+	  benefit. (see DEBUG_INFO_VTA)
-+
-+config DEBUG_INFO_VTA
-+	bool "Enable var-tracking-assignments for debuginfo"
-+	depends on DEBUG_INFO
-+	help
-+	  Enable gcc -fvar-tracking-assignments for improved debug
-+	  information on variable locations in optimized code.  Per
-+	  gcc, DEBUG_INFO_DWARF4 is recommended for best use of VTA.
-+
-+	  VTA has been implicated in codegen bugs (gcc PR61801,
-+	  PR61904), so this may deserve some caution.  One can set
-+	  GCC_COMPARE_DEBUG=-fvar-tracking-assignments-toggle in the
-+	  environment to automatically compile everything both ways,
-+	  generating an error if anything differs.
- 
- config DEBUG_INFO_BTF
- 	bool "Generate BTF typeinfo"
--- 
-2.20.1
-