https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88021
Bug ID: 88021
Summary: aarch64 Busy hang running testcase pr60183.c since
revision 265914
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: testsuite
Assignee: unassigned at gcc dot gnu.org
Reporter: matmal01 at gcc dot gnu.org
Target Milestone: ---
Since revision 265914, the testcase pr60183.c has been FAILing on
aarch64-none-linux-gnu regression tests with a timeout.
Some initial debugging has shown this is a busy hang in
lambda_matrix_right_hermite.
The inner "while (S[i][j] != 0)" loop never gets out of i == 1, j == 0.
(v) hw-a20-6:~ [11:10:29] % gcc-install/bin/native-gcc
/home/matmal01/gcc-source/gcc/testsuite/gcc.dg/torture/pr60183.c
-fno-diagnostics-show-caret -fno-diagnostics-show-line-numbers
-fdiagnostics-color=never -O3 -fomit-frame-pointer -funroll-loops
-fpeel-loops -ftracer -finline-functions -lm -o ./pr60183.exe -wrapper
gdb,-q,--args
Reading symbols from
/home/matmal01/gcc-install/libexec/gcc/aarch64-unknown-linux-gnu/9.0.0/cc1...done.
(gdb) run
Starting program:
/home/matmal01/gcc-install/libexec/gcc/aarch64-unknown-linux-gnu/9.0.0/cc1
-quiet -imultiarch aarch64-linux-gnu
/home/matmal01/gcc-source/gcc/testsuite/gcc.dg/torture/pr60183.c -quiet
-dumpbase pr60183.c -mlittle-endian -mabi=lp64 -auxbase pr60183 -O3
-fdiagnostics-color=never -fno-diagnostics-show-caret
-fno-diagnostics-show-line-numbers -fomit-frame-pointer -funroll-loops
-fpeel-loops -ftracer -finline-functions -o /tmp/ccy2hzG0.s
^C
Program received signal SIGINT, Interrupt.
0x00000000013e54f8 in lambda_matrix_right_hermite (n=<optimized out>,
U=<optimized out>, S=<optimized out>, m=<optimized out>, A=<optimized out>) at
../../gcc-source/gcc/tree-data-ref.c:3500
3500 a = S[i-1][j];
(gdb) print i
$1 = 1
(gdb) print j
$2 = 0
(gdb) cont
Continuing.
Wait for a while^M^C
Program received signal SIGINT, Interrupt.
0x00000000013e54f8 in lambda_matrix_right_hermite (n=<optimized out>,
U=<optimized out>, S=<optimized out>, m=<optimized out>, A=<optimized out>) at
../../gcc-source/gcc/tree-data-ref.c:3500
3500 a = S[i-1][j];
(gdb) print i
$3 = 1
(gdb) print j
$4 = 0
(gdb) next
3502 sigma = (a * b < 0) ? -1: 1;
