[Buildroot] [PATCH 1/1] package/valgrind: Add a setting for LTO build

[Gleb Mazovetskiy]

Valgrind LTO build takes over an hour on my Ryzen 3950x.

This is not always worth it for the ~10% size reduction and a small
performance improvement it offers (see https://www.valgrind.org/docs/manual/dist.news.html)

Adds a new `BR2_VALGRIND_ENABLE_LTO` setting to control LTO enablement
for Valgrind separately from the global BR2_GCC_ENABLE_LTO setting.

Signed-off-by: Gleb Mazovetskiy <glex.spb at gmail.com>
---
 package/valgrind/Config.in   | 10 ++++++++++
 package/valgrind/valgrind.mk |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/package/valgrind/Config.in b/package/valgrind/Config.in
index 56e4af21fa..eff54e7949 100644
--- a/package/valgrind/Config.in
+++ b/package/valgrind/Config.in
@@ -84,4 +84,14 @@ config BR2_PACKAGE_VALGRIND_NULGRIND
 	help
 	  This option allows to install the Nulgrind tool
 
+if BR2_GCC_ENABLE_LTO
+
+config BR2_VALGRIND_ENABLE_LTO
+	bool "Build Valgrind with link-time optimization"
+	help
+	  This produces a faster / smaller valgrind (up to 10%) at the cost
+	  of massively increased build time (can be over an hour).
+
+endif
+
 endif
diff --git a/package/valgrind/valgrind.mk b/package/valgrind/valgrind.mk
index b87e1e518f..07fb1f7d42 100644
--- a/package/valgrind/valgrind.mk
+++ b/package/valgrind/valgrind.mk
@@ -50,7 +50,7 @@ VALGRIND_CONF_OPTS += \
 	--host=$(patsubst arm-%,armv7-%,$(GNU_TARGET_NAME))
 endif
 
-ifeq ($(BR2_GCC_ENABLE_LTO),y)
+ifeq ($(BR2_VALGRIND_ENABLE_LTO),y)
 VALGRIND_CONF_OPTS += --enable-lto
 else
 VALGRIND_CONF_OPTS += --disable-lto
-- 
2.27.0