[PATCH] firmware: Detect whether the toolchain supports pie and automatically disable the FW_PIC option

[Xiang W]

Signed-off-by: Xiang W <wxjstz at 126.com>
---
 firmware/objects.mk         |  4 +++-
 scripts/toolchain-check-pie | 16 ++++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100755 scripts/toolchain-check-pie

diff --git a/firmware/objects.mk b/firmware/objects.mk
index ce91c2f..020e1a9 100644
--- a/firmware/objects.mk
+++ b/firmware/objects.mk
@@ -16,7 +16,9 @@ firmware-ldflags-y +=
 ifndef FW_PIC
 FW_PIC := y
 endif
-
+ifeq ($(FW_PIC),y)
+FW_PIC := $(shell scripts/toolchain-check-pie $(CC))
+endif
 ifeq ($(FW_PIC),y)
 firmware-genflags-y +=	-DFW_PIC
 firmware-asflags-y  +=	-fpic
diff --git a/scripts/toolchain-check-pie b/scripts/toolchain-check-pie
new file mode 100755
index 0000000..14ad6d1
--- /dev/null
+++ b/scripts/toolchain-check-pie
@@ -0,0 +1,16 @@
+#! /bin/bash
+
+CC=$1
+f=$(mktemp)
+mv ${f} ${f}.s
+
+cat << EOF >${f}.s
+	.section .entry, "ax", %progbits
+	.align 3
+	.globl _start
+_start:
+    j   _start
+EOF
+
+${CC}  -nostdlib -fPIE -Wl,-pie ${f}.s -o /dev/null 2>/dev/null && echo y || echo n
+rm ${f}.s
\ No newline at end of file
-- 
2.30.2