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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260308224121.56affbf7@pumpkin> Hi David, On 2026-03-08 22:41:21+0000, David Laight wrote: > On Sun, 8 Mar 2026 22:01:19 +0100 > Thomas Weißschuh wrote: > > On 2026-03-08 11:37:25+0000, david.laight.linux@gmail.com wrote: > > > From: David Laight > > > David Laight (17): > > > tools/nolibc: Add _NOLIBC_OPTIMIZER_HIDE_VAR() to compiler.h > > > selftests/nolibc: Rename w to written in expect_vfprintf() > > > tools/nolibc: Implement strerror() in terms of strerror_r() > > > tools/nolibc: Rename the 'errnum' parameter to strerror() > > > tools/nolibc/printf: Output pad characters in 16 byte chunks > > > tools/nolibc/printf: Simplify __nolibc_printf() > > > tools/nolibc/printf: Use goto and reduce indentation > > > tools/nolibc/printf: Use bit-masks to hold requested flag, length and > > > conversion chars > > > tools/nolibc/printf: Add support for length modifiers tzqL and formats > > > iX > > > tools/nolibc/printf: Handle "%s" with the numeric formats > > > tools/nolibc/printf: Prepend sign to converted number > > > tools/nolibc/printf: Add support for conversion flags space and plus > > > tools/nolibc/printf: Special case 0 and add support for %#x > > > tools/nolibc/printf: Add support for left aligning fields > > > tools/nolibc/printf: Add support for zero padding and field precision > > > tools/nolibc/printf: Add support for octal output > > > > Beginning from here we have another sign-compare warning: > > > > /home/t-8ch/.cache/crosstools/gcc-13.2.0-nolibc/i386-linux/bin/i386-linux-gcc -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -W -Wall -Wextra -fno-stack-protector -Wmissing-prototypes -fstack-protector-all -mstack-protector-guard=global -fsanitize=undefined -fsanitize-trap=all -m32 -Werror -Wl,--fatal-warnings -o nolibc-test \ > > -nostdlib -nostdinc -static -Isysroot/i386/include nolibc-test.c nolibc-test-linkage.c -lgcc > > In file included from sysroot/i386/include/nolibc.h:123, > > from sysroot/i386/include/stdio.h:8, > > from nolibc-test.c:12: > > sysroot/i386/include/stdio.h: In function '__nolibc_printf': > > sysroot/i386/include/stdio.h:569:41: error: comparison of integer expressions of different signedness: 'unsigned int' and 'char' [-Werror=sign-compare] > > 569 | if (sign_prefix != *out) { > > | ^~ > > cc1: all warnings being treated as errors > > > > I have applied all of the patches *before* > > "tools/nolibc/printf: Prepend sign to converted number", which > > introduced the sign_prefix variable. > > > > Could you fix this up and repost the remaining patches? > > I hate 'sign compare' ... > I dislike using casts to 'fix' it - random 'integer' casts have caused me > grief in the past. > I don't want to make 'sign_prefix' signed - stops you adding 4 characters > (should you so desire); not to mention >> being either UB or implementation > defined on signed values (or maybe just negative ones). Sorry for the long delay, I missed these mails. > > The two obvious fixes are: > if (sign_prefix - *out) I went with this and applied the rest of the series. Thanks for all your patches! > or: > if (sign_prefix != *out + 0u) > > Your pick :-) > > At least it is only the last couple of patches. Thomas