CC3220SF_LAUNCHXL: keep ulDebugHeader symbol in LTO builds

maciejbocianski · maciejbocianski · commit a761ec57fd19 · 2020-02-04T12:29:54.000+01:00
Add a "used" attribute to ulDebugHeader (placed in signature_section section)
to fix ARMC6 build with the "-flto" flag. (Error: L6236E: No section matches
selector - no section to be FIRST/LAST. )

This attribute, attached to a function, means that code must be emitted
for the function even if it appears that the function is not referenced.
diff --git a/targets/TARGET_TI/TARGET_CC32XX/TARGET_CC3220SF/TARGET_CC3220SF_LAUNCHXL/CC3220SF_LAUNCHXL.c b/targets/TARGET_TI/TARGET_CC32XX/TARGET_CC3220SF/TARGET_CC3220SF_LAUNCHXL/CC3220SF_LAUNCHXL.c
@@ -336,7 +336,7 @@ void CC3220SF_LAUNCHXL_initGeneral(void)
 }
 
 #if defined TOOLCHAIN_ARM
-__attribute__((section("signature_section")))
+__attribute__((section("signature_section"), used))
 #elif defined TOOLCHAIN_IAR
 #pragma default_variable_attributes = @ ".dbghdr"
 #elif defined TOOLCHAIN_GCC_ARM

Original file line number	Diff line number	Diff line change
`@@ -336,7 +336,7 @@ void CC3220SF_LAUNCHXL_initGeneral(void)`
`336`	`336`	`}`
`337`	`337`
`338`	`338`	`#if defined TOOLCHAIN_ARM`
`339`		`-__attribute__((section("signature_section")))`
	`339`	`+__attribute__((section("signature_section"), used))`
`340`	`340`	`#elif defined TOOLCHAIN_IAR`
`341`	`341`	`#pragma default_variable_attributes = @ ".dbghdr"`
`342`	`342`	`#elif defined TOOLCHAIN_GCC_ARM`