[XS] Change in coreboot[master]: acpi/acpigen.c: Be explicit about char sign

[Felix Held (Code Review)]

Felix Held has submitted this change. ( https://review.coreboot.org/c/coreboot/+/76006?usp=email )

Change subject: acpi/acpigen.c: Be explicit about char sign
......................................................................

acpi/acpigen.c: Be explicit about char sign

The sign of 'char' is not standardized and with GCC is architecture
dependent.

This fixes warnings when compiling this file on arm64.

Signed-off-by: Arthur Heymans 
Change-Id: I53b99835b2ffec5d752fc531fd59e4715f61aced
Reviewed-on: https://review.coreboot.org/c/coreboot/+/76006
Reviewed-by: Felix Singer 
Tested-by: build bot (Jenkins) 
---
M src/acpi/acpigen.c
1 file changed, 1 insertion(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Felix Singer: Looks good to me, approved

diff --git a/src/acpi/acpigen.c b/src/acpi/acpigen.c
index fb92b89..e61954f 100644
--- a/src/acpi/acpigen.c
+++ b/src/acpi/acpigen.c
@@ -187,7 +187,7 @@
    acpigen_write_len_f();
    acpigen_write_integer(len);
    for (size_t i = 0; i < len; i++) {
-		const char c = string[i];
+		const signed char c = string[i];
    	/* Simple ASCII to UTF-16 conversion, replace non ASCII characters */
    	acpigen_emit_word(c >= 0 ? c : '?');
    }