Build failed on one Windows 11 machine but succeeded on the other.

[achen2556]

I'm running into a strange issue: the following function compiles cleanly on one machine but triggers a compiler error on another. Both machines are running the same version of STM32CubeIDE (2.0.0), and the project is shared via a Git repo on Azure DevOps.

Here is the function in question:

#ifdef __cplusplus
extern "C" {
#endif

#include "aws_iot_json_utils.h"
#include <stdio.h>
#include <inttypes.h>
#include <stdint.h>
#include <string.h>
#include <stm32l4xx.h>

IoT_Error_t parseUnsignedInteger8Value(uint8_t *i, const char *jsonString, jsmntok_t *token) {
	if(token->type != JSMN_PRIMITIVE) {
		IOT_WARN("Token was not an integer");
		return JSON_PARSE_ERROR;
	}

	if(('-' == (char) (jsonString[token->start])) || (1 != sscanf(jsonString + token->start, "%" SCNu8, i))) {
		IOT_WARN("Token was not an unsigned integer.");
		return JSON_PARSE_ERROR;
	}

	return SUCCESS;
}

And here is the compiler error:

../Controller/mqtt/aws_iot_json_utils.c:84:101: error: expected ')' before 'SCNu8'

84 | if(('-' == (char) (jsonString[token->start])) || (1 != sscanf(jsonString + token->start, "%" SCNu8, i))) {

| ~ ^~~~~~

|

What am I missing?

I'm trying to understand why one machine accepts the SCNu8 macro from <inttypes.h> while the other rejects it, even though both environments should be identical. Any ideas on what could cause this discrepancy? Thanks.

[KnarfB]

> What am I missing?

a comma after  "%" .

hth

KnarfB

[achen2556]

If that's the case, it would fail on both machines. 

I actually can fix the compile error by adding the preprocessor macro _WANT_IO_C99_FORMATS to this particular file. However, on the other machine, I don't have to, and that's the puzzle.

[KnarfB]

I see. Maybe this one helps: Solved: SCNu8 formatting - STMicroelectronics Community