[Buildroot] [PATCH 1/3] package/gcc: disable libcilkrts when there is no thread support

[Thomas Petazzoni]

The libcilkrts configure script errors out with "Pthreads are required
to build libcilkrts" if the C library doesn't have thread support. To
fix that, we disable libcilkrts when thread support is not available.

This issue was not noticed until now, because we only regularly build
a no-thread toolchain for ARM, and libcilkrts was enabled on ARM only
starting in gcc 7.x.

This fixes the build of no-thread toolchains on architectures where
libcilkrts is supported, i.e x86/x86-64, ARM and Sparc.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
---
 package/gcc/gcc-final/gcc-final.mk | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/package/gcc/gcc-final/gcc-final.mk b/package/gcc/gcc-final/gcc-final.mk
index 9897d18682..1be0b9bfc9 100644
--- a/package/gcc/gcc-final/gcc-final.mk
+++ b/package/gcc/gcc-final/gcc-final.mk
@@ -81,6 +81,11 @@ ifeq ($(BR2_sparc),y)
 HOST_GCC_FINAL_CONF_OPTS += --disable-libcilkrts
 endif
 
+# Pthreads are required to build libcilkrts
+ifeq ($(BR2_PTHREADS_NONE),y)
+HOST_GCC_FINAL_CONF_OPTS += --disable-libcilkrts
+endif
+
 # Disable shared libs like libstdc++ if we do static since it confuses linking
 # In that case also disable libcilkrts as there is no static version
 ifeq ($(BR2_STATIC_LIBS),y)
-- 
2.14.4