https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115840
Bug ID: 115840
Summary: RISC-V with V:‘({anonymous})’ may be used
uninitialized
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: syq at gcc dot gnu.org
Target Milestone: ---
When I build glibc with V extension enabled, I get such a error
../sysdeps/unix/sysv/linux/getloadavg.c: In function ‘getloadavg’:
../sysdeps/unix/sysv/linux/getloadavg.c:43:41: error: ‘({anonymous})’ may be
used uninitialized [-Werror=maybe-uninitialized]
43 | loadavg[i] = (double) info.loads[i] / SYSINFO_LOADS_SCALE;
| ^
../sysdeps/unix/sysv/linux/getloadavg.c:33:1: note: ‘({anonymous})’ was
declared here
33 | getloadavg (double loadavg[], int nelem)
| ^~~~~~~~~~
cc1: all warnings being treated as errors
The cmdline is
/home/syq/gcc/build-rv/gcc/xgcc -B/home/syq/gcc/build-rv/gcc
-B/usr/riscv64-linux-gnu -march=rv64imafdcv
../sysdeps/unix/sysv/linux/getloadavg.c -c -std=gnu11 -fgnu89-inline -g -O2
-Wall -Wwrite-strings -Wundef -Werror -fmerge-all-constants -frounding-math
-fno-stack-protector -fno-common -Wp,-U_FORTIFY_SOURCE -Wstrict-prototypes
-Wold-style-definition -fmath-errno -fPIE -ftls-model=initial-exec
-I../include -I/home/syq/glibc/build-rv/misc -I/home/syq/glibc/build-rv
-I../sysdeps/unix/sysv/linux/riscv/rv64
-I../sysdeps/unix/sysv/linux/riscv/include -I../sysdeps/unix/sysv/linux/riscv
-I../sysdeps/riscv/nptl -I../sysdeps/unix/sysv/linux/wordsize-64
-I../sysdeps/unix/sysv/linux/riscv/multiarch
-I../sysdeps/unix/sysv/linux/include -I../sysdeps/unix/sysv/linux
-I../sysdeps/nptl -I../sysdeps/pthread -I../sysdeps/gnu
-I../sysdeps/unix/inet -I../sysdeps/unix/sysv -I../sysdeps/unix
-I../sysdeps/posix -I../sysdeps/riscv/rv64/rvd -I../sysdeps/riscv/rv64/rvf
-I../sysdeps/riscv/rvf -I../sysdeps/riscv/rvd -I../sysdeps/riscv/rv64
-I../sysdeps/riscv/multiarch -I../sysdeps/riscv -I../sysdeps/ieee754/ldbl-128
-I../sysdeps/ieee754/dbl-64 -I../sysdeps/ieee754/flt-32
-I../sysdeps/wordsize-64 -I../sysdeps/ieee754 -I../sysdeps/generic -I..
-I../libio -I. -D_LIBC_REENTRANT -include
/home/syq/glibc/build-rv/libc-modules.h -DMODULE_NAME=libc -include
../include/libc-symbols.h -DPIC -DTOP_NAMESPACE=glibc -o
/home/syq/glibc/build-rv/misc/getloadavg.o -MD -MP -MF
/home/syq/glibc/build-rv/misc/getloadavg.o.dt -MT
/home/syq/glibc/build-rv/misc/getloadavg.o
I tested with GCC14.1 and current master, both of them have this problem.
If I use `-march=rv64imafdcv`, the problem won't happen.
