Merge pull request #21443 from maribu/tree-wide/gcc-15-1-fixes

tree-wide: fix compilation with GCC 15.1 and picolibc 1.8.10

core/lib/include/compiler_hints.h

@@ -33,11 +33,25 @@ extern "C" {
  *        cannot return.
  */
 #ifndef NORETURN
-#ifdef __GNUC__
-#define NORETURN  __attribute__((noreturn))
-#else
-#define NORETURN
+#  ifdef __GNUC__
+#    define NORETURN __attribute__((noreturn))
+#  else
+#    define NORETURN
+#  endif
 #endif
+
+/**
+ * @def NONSTRING
+ * @brief The `NONSTRING` keyword tells the compiler to assume that a char array
+ *        is not used as c string. (Specifically: It does not need a terminating
+ *        zero byte.)
+ */
+#ifndef NONSTRING
+#  if (__GNUC__ >= 15)
+#    define NONSTRING __attribute__((nonstring))
+#  else
+#    define NONSTRING
+#  endif
 #endif
 
 /**
@@ -48,11 +62,11 @@ extern "C" {
  *        optimization just as an arithmetic operator would be.
  */
 #ifndef PURE
-#ifdef __GNUC__
-#define PURE  __attribute__((pure))
-#else
-#define PURE
-#endif
+#  ifdef __GNUC__
+#    define PURE __attribute__((pure))
+#  else
+#    define PURE
+#  endif
 #endif
 
 /**
@@ -61,11 +75,11 @@ extern "C" {
  *        static functions, function arguments, local variables
  */
 #ifndef MAYBE_UNUSED
-#ifdef __GNUC__
-#define MAYBE_UNUSED  __attribute__((unused))
-#else
-#define MAYBE_UNUSED
-#endif
+#  ifdef __GNUC__
+#    define MAYBE_UNUSED __attribute__((unused))
+#  else
+#    define MAYBE_UNUSED
+#  endif
 #endif
 
 /**
@@ -77,9 +91,9 @@ extern "C" {
  *            by llvm.
  */
 #if defined(__llvm__) || defined(__clang__)
-#define NO_SANITIZE_ARRAY __attribute__((no_sanitize("address")))
+#  define NO_SANITIZE_ARRAY __attribute__((no_sanitize("address")))
 #else
-#define NO_SANITIZE_ARRAY
+#  define NO_SANITIZE_ARRAY
 #endif
 
 /**
@@ -90,9 +104,9 @@ extern "C" {
  *            an assembler instruction causes a longjmp, or a write causes a reboot.
  */
 #if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ >= 5) || defined(__clang__)
-#define UNREACHABLE() __builtin_unreachable()
+#  define UNREACHABLE() __builtin_unreachable()
 #else
-#define UNREACHABLE() do { /* nothing */ } while (1)
+#  define UNREACHABLE()  do { /* nothing */ } while (1)
 #endif
 
 /**
@@ -138,12 +152,12 @@ extern "C" {
  * This allows providing two different implementations in C, with one being
  * more efficient if constant folding is used.
  */
-#define IS_CT_CONSTANT(expr) <IMPLEMENTATION>
+#  define IS_CT_CONSTANT(expr) <IMPLEMENTATION>
 #elif defined(__GNUC__)
 /* both clang and gcc (which both define __GNUC__) support this */
-#define IS_CT_CONSTANT(expr) __builtin_constant_p(expr)
+#  define IS_CT_CONSTANT(expr) __builtin_constant_p(expr)
 #else
-#define IS_CT_CONSTANT(expr) 0
+#  define IS_CT_CONSTANT(expr) 0
 #endif
 
 /**
@@ -175,9 +189,9 @@ extern "C" {
  * @param[in] cond  Condition that is guaranteed to be true
  */
 #ifdef NDEBUG
-#define assume(cond)    ((cond) ? (void)0 : UNREACHABLE())
+#  define assume(cond) ((cond) ? (void)0 : UNREACHABLE())
 #else
-#define assume(cond)    assert(cond)
+#  define assume(cond) assert(cond)
 #endif
 
 /**

makefiles/vars.inc.mk

@@ -23,6 +23,7 @@ export NATIVEINCLUDES        # The native include paths, set by the various nati
 
 export GCC_C_INCLUDES        # system include dirs implicitly used by GCC's c compiler, only defined with TOOLCHAIN=llvm
 export GCC_CXX_INCLUDES      # system include dirs implicitly used by GCC's c++ compiler, only defined with TOOLCHAIN=llvm
+export GCC_VERSION           # version of GCC if GCC is used, empty otherwise
 
 export USEMODULE             # Sys Module dependencies of the application. Set in the application's Makefile.
 export BIN_USEMODULE         # Modules specific to bindist (see bindist.ink.mk). Set in the application's Makefile.

pkg/pkg.mk

@@ -197,6 +197,16 @@ distclean:: clean
 endif
 
 # Disabling some diagnostics: These issues needs to be fixed upstream
+CFLAGS += -Wno-maybe-uninitialized
 ifeq (llvm,$(TOOLCHAIN))
   CFLAGS += -Wno-documentation
 endif
+
+include $(RIOTBASE)/makefiles/utils/strings.mk
+# Disabling -Wunterminated-string-initialization on toolchains that support this
+# warning
+ifeq (1,$(call version_is_greater_or_equal,$(GCC_VERSION),15))
+  CFLAGS += -Wno-unterminated-string-initialization
+  # this flag should not be passed to g++, only gcc:
+  CXXUWFLAGS += -Wno-unterminated-string-initialization
+endif

sys/fmt/fmt.c

@@ -27,12 +27,14 @@
 #include <time.h>
 #include <unistd.h>
 
+#include "compiler_hints.h"
 #include "container.h"
 #include "fmt.h"
 #include "modules.h"
 
 extern ssize_t stdio_write(const void* buffer, size_t len);
 
+NONSTRING
 static const char _hex_chars[16] = "0123456789ABCDEF";
 
 static const uint32_t _tenmap[] = {

sys/fmt/table.c

@@ -24,9 +24,11 @@
 #include <unistd.h>
 #include <string.h>
 
+#include "compiler_hints.h"
 #include "fmt.h"
 #include "fmt_table.h"
 
+NONSTRING
 static const char fmt_table_spaces[16] = "                ";
 
 /**

sys/picolibc_syscalls_default/syscalls.c

@@ -238,7 +238,9 @@ static int picolibc_get(FILE *file)
 FILE picolibc_stdio =
     FDEV_SETUP_STREAM(picolibc_put, picolibc_get, picolibc_flush, _FDEV_SETUP_RW);
 
-#ifdef PICOLIBC_STDIO_GLOBALS
+/* Since picolibc 1.8.10, PICOLIBC_STDIO_GLOBALS is prefixed with two leading
+ * underscores. We just test for both to remain backwards compatible */
+#if defined(PICOLIBC_STDIO_GLOBALS) || defined(__PICOLIBC_STDIO_GLOBALS)
 #ifdef __strong_reference
 /* This saves two const pointers.
  * See https://github.com/RIOT-OS/RIOT/pull/17001#issuecomment-945936918

tests/bench/sys_base64/main.c

@@ -22,15 +22,20 @@
 #include <string.h>
 
 #include "base64.h"
+#include "compiler_hints.h"
 #include "fmt.h"
 #include "macros/utils.h"
 #include "xtimer.h"
 
 static char buf[128];
 
+/* no need for the zero-termination here, base64_encode() gets the size of the
+ * string as explicit argument */
+NONSTRING
 static const char input[96] = "This is an extremely, enormously, greatly, "
                               "immensely, tremendously, remarkably lengthy "
                               "sentence!";
+NONSTRING
 static const char base64[128] =
 "VGhpcyBpcyBhbiBleHRyZW1lbHksIGVub3Jtb3VzbHksIGdyZWF0bHksIGltbWVuc2VseSwgdHJl"
 "bWVuZG91c2x5LCByZW1hcmthYmx5IGxlbmd0aHkgc2VudGVuY2Uh";

tests/drivers/hm330x/Makefile

@@ -7,5 +7,6 @@ USEMODULE += $(DRIVER)
 USEMODULE += ztimer_usec
 USEMODULE += ztimer_msec
 USEMODULE += fmt
+USEMODULE += fmt_table
 
 include $(RIOTBASE)/Makefile.include

tests/drivers/hm330x/main.c

@@ -13,40 +13,19 @@
  * @file
  * @brief       HM330X driver test application
  *
- * @author      Marian Buschsieweke <marian.buschsieweke@ovgu.de>
  * @author      Francisco Molina <francois-xavier.molinas@inria.fr>
  *
  * @}
  */
 
-#include <stdio.h>
-#include <string.h>
-
 #include "fmt.h"
+#include "fmt_table.h"
+#include "time_units.h"
 #include "ztimer.h"
-#include "timex.h"
 
 #include "hm330x.h"
 #include "hm330x_params.h"
 
-static const char spaces[16] = "                ";
-
-static void print_col_u32_dec(uint32_t number, size_t width)
-{
-    char sbuf[10]; /* "4294967295" */
-    size_t slen;
-
-    slen = fmt_u32_dec(sbuf, number);
-    if (width > slen) {
-        width -= slen;
-        while (width > sizeof(spaces)) {
-            print(spaces, sizeof(spaces));
-        }
-        print(spaces, width);
-    }
-    print(sbuf, slen);
-}
-
 int main(void)
 {
     hm330x_t dev;

tests/sys/psa_crypto/main.c

@@ -20,6 +20,7 @@
 
 #include <stdio.h>
 #include "embUnit.h"
+#include "compiler_hints.h"
 #include "psa/crypto.h"
 
 void addFailurePSA(const char *func, psa_status_t errcode, long line, const char *file)
@@ -73,7 +74,9 @@ static void test_hash_interleaved(void)
 {
     const psa_algorithm_t alg = PSA_ALG_SHA_256;
 
+    NONSTRING
     const uint8_t in1[1] = "a";
+    NONSTRING
     const uint8_t in2[1] = "b";
 
     const uint8_t exp1[] = {

tests/sys/psa_crypto_ecdsa/test_ecdsa_p256_vectors.c

@@ -20,6 +20,7 @@
 #include <stdio.h>
 #include <stdint.h>
 
+#include "compiler_hints.h"
 #include "psa/crypto.h"
 
 /*
@@ -42,6 +43,7 @@ static const uint8_t public_key[] = {0x04, 0x60, 0xFE, 0xD4, 0xBA, 0x25, 0x5A, 0
 
 /* certain PSA backends require the data to be in RAM rather than ROM
  * so these values cannot be `const` */
+NONSTRING
 static uint8_t message[6] = "sample";
 static uint8_t signature[] = {0xEF, 0xD4, 0x8B, 0x2A, 0xAC, 0xB6, 0xA8, 0xFD, 0x11, 0x40,
     0xDD, 0x9C, 0xD4, 0x5E, 0x81, 0xD6, 0x9D, 0x2C, 0x87, 0x7B, 0x56, 0xAA, 0xF9, 0x91, 0xC3, 0x4D,

tests/sys/struct_tm_utility/main.c

@@ -29,17 +29,21 @@
 #include <stdlib.h>
 #include <stdbool.h>
 
+#include "compiler_hints.h"
 #include "shell.h"
 #include "tm.h"
 
+NONSTRING
 static const char MON_NAMES[12][3] = {
     "JAN", "FEB", "MAR", "APR",
     "MAY", "JUN", "JUL", "AUG",
     "SEP", "OCT", "NOV", "DEC",
 };
+NONSTRING
 static const char DAY_NAMES[7][3] = {
     "SUN", "MON", "TUE", "WED", "THU", "FRI", "SAT"
 };
+NONSTRING
 static const char BOOL_NAMES[2][3] = { "NO", "YES" };
 
 bool proper_atoi(const char *a, int *i)

tests/unittests/tests-fmt/tests-fmt.c

@@ -17,6 +17,7 @@
 
 #include "embUnit/embUnit.h"
 
+#include "compiler_hints.h"
 #include "fmt.h"
 #include "tests-fmt.h"
 
@@ -244,6 +245,7 @@ static void test_fmt_hex_bytes(void)
 
 static void test_fmt_u16_hex(void)
 {
+    NONSTRING
     char out[8] = "zzzzzzzz";
 
     /* Check return count with null buffer input */
@@ -260,6 +262,7 @@ static void test_fmt_u16_hex(void)
 
 static void test_fmt_u32_hex(void)
 {
+    NONSTRING
     char out[12] = "zzzzzzzzzzzz";
 
     /* Check return count with null buffer input */
@@ -276,6 +279,7 @@ static void test_fmt_u32_hex(void)
 
 static void test_fmt_u64_hex(void)
 {
+    NONSTRING
     char out[20] = "zzzzzzzzzzzzzzzzzzzz";
 
     /* Check return count with null buffer input */
@@ -292,6 +296,7 @@ static void test_fmt_u64_hex(void)
 
 static void test_fmt_u16_dec(void)
 {
+    NONSTRING
     char out[8] = "zzzzzzzz";
     uint8_t chars = 0;
 
@@ -310,6 +315,7 @@ static void test_fmt_u16_dec(void)
 
 static void test_fmt_u32_dec(void)
 {
+    NONSTRING
     char out[16] = "zzzzzzzzzzzzzzzz";
     uint8_t chars = 0;
 
@@ -329,6 +335,7 @@ static void test_fmt_u32_dec(void)
 
 static void test_fmt_u64_dec(void)
 {
+    NONSTRING
     char out[24] = "zzzzzzzzzzzzzzzzzzzzzzzz";
     uint8_t chars = 0;
 
@@ -345,6 +352,7 @@ static void test_fmt_u64_dec(void)
 
 static void test_fmt_u64_dec_zero(void)
 {
+    NONSTRING
     char out[24] = "zzzzzzzzzzzzzzzzzzzzzzzz";
     uint8_t chars = 0;
 
@@ -355,6 +363,7 @@ static void test_fmt_u64_dec_zero(void)
 
 static void test_fmt_u64_dec_u64max(void)
 {
+    NONSTRING
     char out[24] = "zzzzzzzzzzzzzzzzzzzzzzzz";
     uint8_t chars = 0;