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gcc/15 libestdc++: drop sprintf/strcpy ld warnings
On Sun, 14 Sep 2025 19:36:07 +0200, Jeremie Courreges-Anglas wrote:
> On Sun, Sep 14, 2025 at 05:51:17PM +0200, Jeremie Courreges-Anglas wrote:
> >
> > ld.bfd spots it with a "hello, world!" program, ld.lld doesn't. The
> > sprintf_ld() change is adapted from code already in lang/gcc/15.
> > Since that function is internal, it's not a problem.
> >
> > With this, eg++ (-fuse-ld=bfd) doesn't warn about the sprintf use.
> > This matters for some overly picky ports that fail to find a working
> > C++ compiler when ld(1) spits any warning. Diff for gcc/15 to follow.
>
> Same for gcc/15 where more occurrences have crept up.
>
> ok?
OK.
>
> Index: Makefile
> ===================================================================
> RCS file: /home/cvs/ports/lang/gcc/15/Makefile,v
> diff -u -p -r1.6 Makefile
> --- Makefile 13 Sep 2025 14:45:15 -0000 1.6
> +++ Makefile 14 Sep 2025 16:00:49 -0000
> @@ -16,6 +16,8 @@ V = 15.2.0
> FULL_VERSION = $V
> FULL_PKGVERSION = $V
>
> +REVISION = 0
> +
> ADASTRAP-amd64 = adastrap-amd64-11.2.0-5.tar.xz
> ADASTRAP-arm = adastrap-arm-4.9.4-0.tar.xz
> ADASTRAP-hppa = adastrap-hppa-8.3.0-1.tar.xz
> Index: patches/patch-libiberty_cp-demangle_c
> ===================================================================
> RCS file: /home/cvs/ports/lang/gcc/15/patches/patch-libiberty_cp-demangle_c,v
> diff -u -p -r1.1.1.1 patch-libiberty_cp-demangle_c
> --- patches/patch-libiberty_cp-demangle_c 18 Aug 2025 19:49:24 -0000 1.1.1.1
> +++ patches/patch-libiberty_cp-demangle_c 14 Sep 2025 17:33:56 -0000
> @@ -1,12 +1,25 @@
> +Avoid using sprintf and strcpy: aside from their unsafety they trigger ld(1)
> +warnings, leading to broken feature detection when linking test
> +programs with libestdc++.
> +
> Index: libiberty/cp-demangle.c
> --- libiberty/cp-demangle.c.orig
> +++ libiberty/cp-demangle.c
> +@@ -2832,7 +2832,7 @@ cplus_demangle_type (struct d_info *di)
> + &cplus_demangle_builtin_types[34],
> + arg, suffix);
> + d_advance (di, 1);
> +- sprintf (buf, "%d", arg);
> ++ snprintf (buf, sizeof buf, "%d", arg);
> + di->expansion += ret->u.s_extended_builtin.type->len
> + + strlen (buf) + (suffix != 0);
> + break;
> @@ -4618,7 +4618,7 @@ static inline void
> d_append_num (struct d_print_info *dpi, int l)
> {
> char buf[25];
> - sprintf (buf,"%d", l);
> -+ snprintf (buf, 25, "%d", l);
> ++ snprintf (buf, sizeof buf, "%d", l);
> d_append_string (dpi, buf);
> }
>
> Index: patches/patch-libstdc++-v3_src_c++11_debug_cc
> ===================================================================
> RCS file: /home/cvs/ports/lang/gcc/15/patches/patch-libstdc++-v3_src_c++11_debug_cc,v
> diff -u -p -r1.1.1.1 patch-libstdc++-v3_src_c++11_debug_cc
> --- patches/patch-libstdc++-v3_src_c++11_debug_cc 18 Aug 2025 19:49:25 -0000 1.1.1.1
> +++ patches/patch-libstdc++-v3_src_c++11_debug_cc 14 Sep 2025 17:33:28 -0000
> @@ -1,3 +1,7 @@
> +Avoid using sprintf: aside from its unsafety it triggers ld(1)
> +warnings, leading to broken feature detection when linking test
> +programs with libestdc++.
> +
> Index: libstdc++-v3/src/c++11/debug.cc
> --- libstdc++-v3/src/c++11/debug.cc.orig
> +++ libstdc++-v3/src/c++11/debug.cc
> @@ -19,3 +23,30 @@ Index: libstdc++-v3/src/c++11/debug.cc
> print_word(ctx, buf, written);
> }
>
> +@@ -1170,7 +1170,7 @@ namespace
> +
> + PrintContext& ctx = *static_cast<PrintContext*>(data);
> +
> +- int written = __builtin_sprintf(buf, "%p ", (void*)pc);
> ++ int written = __builtin_snprintf(buf, sizeof buf, "%p ", (void*)pc);
> + print_word(ctx, buf, written);
> +
> + int ret = 0;
> +@@ -1198,7 +1198,7 @@ namespace
> +
> + if (lineno)
> + {
> +- written = __builtin_sprintf(buf, ":%u\n", lineno);
> ++ written = __builtin_snprintf(buf, sizeof buf, ":%u\n", lineno);
> + print_word(ctx, buf, written);
> + }
> + else
> +@@ -1221,7 +1221,7 @@ namespace
> + if (errnum > 0)
> + {
> + char buf[64];
> +- int written = __builtin_sprintf(buf, " (errno=%d)\n", errnum);
> ++ int written = __builtin_snprintf(buf, sizeof buf, " (errno=%d)\n", errnum);
> + print_word(ctx, buf, written);
> + }
> + else
> Index: patches/patch-libstdc++-v3_src_c++17_floating_to_chars_cc
> ===================================================================
> RCS file: patches/patch-libstdc++-v3_src_c++17_floating_to_chars_cc
> diff -N patches/patch-libstdc++-v3_src_c++17_floating_to_chars_cc
> --- /dev/null 1 Jan 1970 00:00:00 -0000
> +++ patches/patch-libstdc++-v3_src_c++17_floating_to_chars_cc 14 Sep 2025 17:33:43 -0000
> @@ -0,0 +1,24 @@
> +Avoid using sprintf: aside from its unsafety it triggers ld(1)
> +warnings, leading to broken feature detection when linking test
> +programs with libestdc++.
> +
> +Index: libstdc++-v3/src/c++17/floating_to_chars.cc
> +--- libstdc++-v3/src/c++17/floating_to_chars.cc.orig
> ++++ libstdc++-v3/src/c++17/floating_to_chars.cc
> +@@ -1073,14 +1073,14 @@ namespace
> + {
> + // strfromf128 unfortunately doesn't allow .*
> + char fmt[3 * sizeof(int) + 6];
> +- sprintf(fmt, "%%.%d%c", args..., int(format_string[4]));
> ++ snprintf(fmt, sizeof(fmt), "%%.%d%c", args..., int(format_string[4]));
> + len = __strfromf128(buffer, length, fmt, value);
> + }
> + }
> + else
> + #endif
> + #endif
> +- len = sprintf(buffer, format_string, args..., value);
> ++ len = snprintf(buffer, length, format_string, args..., value);
> +
> + #if _GLIBCXX_USE_C99_FENV_TR1 && defined(FE_TONEAREST)
> + if (saved_rounding_mode != FE_TONEAREST)
> Index: patches/patch-libstdc++-v3_src_c++20_format_cc
> ===================================================================
> RCS file: patches/patch-libstdc++-v3_src_c++20_format_cc
> diff -N patches/patch-libstdc++-v3_src_c++20_format_cc
> --- /dev/null 1 Jan 1970 00:00:00 -0000
> +++ patches/patch-libstdc++-v3_src_c++20_format_cc 14 Sep 2025 17:34:28 -0000
> @@ -0,0 +1,19 @@
> +Avoid using strcpy: aside from its unsafety it triggers ld(1)
> +warnings, leading to broken feature detection when linking test
> +programs with libestdc++.
> +
> +Index: libstdc++-v3/src/c++20/format.cc
> +--- libstdc++-v3/src/c++20/format.cc.orig
> ++++ libstdc++-v3/src/c++20/format.cc
> +@@ -189,8 +189,9 @@ __with_encoding_conversion(const locale& loc)
> + // just don't delete[] it in the locale(locale, Facet*) constructor.
> + if (const char* name = loc._M_impl->_M_names[0])
> + {
> +- loc2._M_impl->_M_names[0] = new char[strlen(name) + 1];
> +- strcpy(loc2._M_impl->_M_names[0], name);
> ++ size_t sz = strlen(name) + 1;
> ++ loc2._M_impl->_M_names[0] = new char[sz];
> ++ strlcpy(loc2._M_impl->_M_names[0], name, sz);
> + }
> + return loc2;
> + }
>
> --
> jca
gcc/15 libestdc++: drop sprintf/strcpy ld warnings