Change in coreboot[master]: [TEST] Enable link time optimization

[Jacob Garber (Code Review)]

Jacob Garber has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/40815 )

Change subject: [TEST] Enable link time optimization
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[TEST] Enable link time optimization

Enable LTO to shake out the bugs.

Current problems:
- GCC does not track symbol origins when using LTO, so it must be
disabled for AGESA so it can be excluded from the illegal_globals check.
- GCC segfaults when compiling ARMV7
- Most of the Google boards do not compile because of a missing
reference to _watchdog_tombstone

Change-Id: I37474d4adbf653729bb2e631a1ff812b4319c17a
Signed-off-by: Jacob Garber 
---
M src/Kconfig
M src/vendorcode/amd/agesa/Makefile.inc
2 files changed, 7 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/15/40815/1

diff --git a/src/Kconfig b/src/Kconfig
index e4821e8..375bca2 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -116,7 +116,7 @@

config LTO
    bool "Use link time optimization (LTO)"
-	default n
+	default y
    depends on COMPILER_GCC
    help
      Compile with link time optimization. This can often decrease the
diff --git a/src/vendorcode/amd/agesa/Makefile.inc b/src/vendorcode/amd/agesa/Makefile.inc
index b96af84..3e4a53c 100644
--- a/src/vendorcode/amd/agesa/Makefile.inc
+++ b/src/vendorcode/amd/agesa/Makefile.inc
@@ -14,6 +14,12 @@

AGESA_CFLAGS := -march=k8-sse3 -mtune=k8-sse3 -fno-strict-aliasing

+# GCC currently does not track symbol origins when using LTO, so
+# AGESA gets caught in the illegal_globals check. Disable for now.
+ifeq ($(CONFIG_LTO),y)
+AGESA_CFLAGS += -fno-lto
+endif
+
 CFLAGS_x86_32 += $(AGESA_CFLAGS)
 CFLAGS_x86_64 += $(AGESA_CFLAGS)

[Branden Waldner (Code Review)]

Attention is currently required from: Jacob Garber.
Branden Waldner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/40815 )

Change subject: [TEST] Enable link time optimization
......................................................................

Patch Set 6:

(1 comment)

This change is ready for review.

Patchset:

PS6: 
I've tested this on my Asus P2B and it seems to work correctly.

[Paul Menzel (Code Review)]

Attention is currently required from: Branden Waldner, Jacob Garber.
Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/40815 )

Change subject: [TEST] Enable link time optimization
......................................................................

Patch Set 6:

(1 comment)

Patchset:

PS6:
> I've tested this on my Asus P2B and it seems to work correctly.

You accidentally removed the WIP tag of this patch. (If you comment, there is a “button” SAVE next to the button with the blue background, and a lot of people clicked on that by accident. So no problem.)