[PATCH 1/1] sandbox: replace putchar(ch) by fputc(ch, stdout)

Heinrich Schuchardt heinrich.schuchardt at canonical.com
Sat Nov 20 13:28:33 CET 2021

When compiled with -Og for better debugability u-boot ends up in a stack
overflow using

    gcc (Ubuntu 11.2.0-7ubuntu2) 11.2.0
    GNU Binutils for Ubuntu 2.37

putchar(ch) is defined as a macro which ends up calling U-Boot's putc()
implementation instead of the glibc one, which calls os_putc() ...

Let's use fputc(ch, stdout) instead as fputc() does not exist in U-Boot.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
 arch/sandbox/cpu/os.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index b72dafca2b..25a04a650a 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -628,7 +628,7 @@ int os_get_filesize(const char *fname, loff_t *size)
 void os_putc(int ch)
-	putchar(ch);
+	fputc(ch, stdout);
 void os_puts(const char *str)

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