[PATCH v2 4/7] selftests/nolibc: not include limits.h for nolibc

[Zhangjin Wu]

When compile nolibc-test.c with 2.31 glibc, we got such error:

    In file included from /usr/riscv64-linux-gnu/include/sys/cdefs.h:452,
                     from /usr/riscv64-linux-gnu/include/features.h:461,
                     from /usr/riscv64-linux-gnu/include/bits/libc-header-start.h:33,
                     from /usr/riscv64-linux-gnu/include/limits.h:26,
                     from /usr/lib/gcc-cross/riscv64-linux-gnu/9/include/limits.h:194,
                     from /usr/lib/gcc-cross/riscv64-linux-gnu/9/include/syslimits.h:7,
                     from /usr/lib/gcc-cross/riscv64-linux-gnu/9/include/limits.h:34,
                     from /labs/linux-lab/src/linux-stable/tools/testing/selftests/nolibc/nolibc-test.c:6:
    /usr/riscv64-linux-gnu/include/bits/wordsize.h:28:3: error: #error "rv32i-based targets are not supported"
       28 | # error "rv32i-based targets are not supported"

Glibc (>= 2.33) commit 5b6113d62efa ("RISC-V: Support the 32-bit ABI
implementation") fixed up above error.

As suggested by Thomas, defining INT_MIN/INT_MAX for nolibc can remove
the including of limits.h, and therefore no above error. of course, the
other libcs still require limits.h, move it to the right place.

The LONG_MIN/LONG_MAX are also defined too.

Suggested-by: Thomas Weißschuh <linux at weissschuh.net>
Link: https://lore.kernel.org/linux-riscv/20230524182431.268908-1-falcon@tinylab.org/T/#
Signed-off-by: Zhangjin Wu <falcon at tinylab.org>
---
 tools/include/nolibc/stdint.h                | 14 ++++++++++++++
 tools/testing/selftests/nolibc/nolibc-test.c |  4 +---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/tools/include/nolibc/stdint.h b/tools/include/nolibc/stdint.h
index c1ce4f5e0603..31a5264539ae 100644
--- a/tools/include/nolibc/stdint.h
+++ b/tools/include/nolibc/stdint.h
@@ -96,4 +96,18 @@ typedef uint64_t          uintmax_t;
 #define UINT_FAST32_MAX  SIZE_MAX
 #define UINT_FAST64_MAX  SIZE_MAX
 
+#ifndef INT_MIN
+#define INT_MIN          (-__INT_MAX__ - 1)
+#endif
+#ifndef INT_MAX
+#define INT_MAX          __INT_MAX__
+#endif
+
+#ifndef LONG_MIN
+#define LONG_MIN         (-__LONG_MAX__ - 1)
+#endif
+#ifndef LONG_MAX
+#define LONG_MAX         __LONG_MAX__
+#endif
+
 #endif /* _NOLIBC_STDINT_H */
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 7f9b716fd9b1..e75ce6b68565 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -2,9 +2,6 @@
 
 #define _GNU_SOURCE
 
-/* platform-specific include files coming from the compiler */
-#include <limits.h>
-
 /* libc-specific include files
  * The program may be built in 3 ways:
  *   $(CC) -nostdlib -include /path/to/nolibc.h => NOLIBC already defined
@@ -39,6 +36,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <unistd.h>
+#include <limits.h>
 #endif
 #endif
 
-- 
2.25.1