Fix format specifier warnings on 32-bit architectures (i686) #3791
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During compilation on i686 (32-bit) architecture with GCC 15, format
specifier warnings appear due to type size differences between 32-bit
and 64-bit platforms.
```
server.c: In function 'on_frame_recv_callback':
warning: format '%ld' expects argument of type 'long int', but argument 14
has type 'size_t' {aka 'unsigned int'} [-Wformat=]
638 | LM_DBG("h2 header [%d], %p %ld\n", frame->hd.type, frame->headers.nva, frame->headers.nvlen);
dm_impl.c: In function 'dm_avps2json':
warning: format '%ld' expects argument of type 'long int', but argument 15
has type 'int64_t' {aka 'long long int'} [-Wformat=]
484 | LM_DBG("%2d. got int64 AVP %s (%u), value: %ld\n", i, dm_avp.avp_name, h->avp_code, h->avp_value->i64);
warning: format '%lu' expects argument of type 'long unsigned int', but argument 15
has type 'uint64_t' {aka 'long long unsigned int'} [-Wformat=]
494 | LM_DBG("%2d. got uint64 AVP %s (%u), value: %lu\n", i, dm_avp.avp_name, h->avp_code, h->avp_value->u64);
```
Type sizes differ between 32-bit and 64-bit architectures:
**On x86_64 (64-bit):**
- `size_t` = `unsigned long` (8 bytes)
- `int64_t` = `long int` (8 bytes)
**On i686 (32-bit):**
- `size_t` = `unsigned int` (4 bytes)
- `int64_t` = `long long int` (8 bytes)
- `uint64_t` = `unsigned long long int` (8 bytes)
Use portable C99 format specifiers that work correctly on all
architectures:
- `%zu` for `size_t` (modules/http2d/server.c line 638)
- `%" PRId64` for `int64_t` (modules/aaa_diameter/dm_impl.c line 484)
- `%" PRIu64` for `uint64_t` (modules/aaa_diameter/dm_impl.c line 494)
Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>
Assisted-by: Claude (Anthropic) <https://claude.ai>
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Summary
Fix format specifier warnings on 32-bit architectures (i686) with GCC 15
Details
This PR fixes compilation warnings that appear on 32-bit architectures (i686) when using GCC 15. The warnings are caused by using incorrect format specifiers for
size_t,int64_t, anduint64_ttypes, which have different sizes on 32-bit vs 64-bit platforms.On x86_64,
size_tandint64_tare aliases forunsigned longandlong intrespectively, so%ldand%luwork fine. However, on i686 (32-bit):size_tisunsigned int(4 bytes), notunsigned longint64_tislong long int(8 bytes), notlong intuint64_tisunsigned long long int(8 bytes), notunsigned long intThis causes GCC to emit
-Wformatwarnings on 32-bit builds, as the format specifiers don't match the actual argument types.Affected modules:
%ldforsize_tin server.c%ld/%luforint64_t/uint64_tin dm_impl.cSolution
Replace architecture-specific format specifiers with portable C99 standard specifiers:
%zuforsize_t(defined in C99, works on all architectures)%" PRId64forint64_t(from<inttypes.h>, expands to correct specifier per platform)%" PRIu64foruint64_t(from<inttypes.h>, expands to correct specifier per platform)These portable specifiers automatically adapt to the platform:
%zu→ format asunsigned long,PRId64→"ld",PRIu64→"lu"%zu→ format asunsigned int,PRId64→"lld",PRIu64→"llu"Compatibility
No compatibility impact. This is purely a build-time fix that doesn't change runtime behavior or APIs. The same values are printed, just with correct format specifiers.
Closing issues
N/A