https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72873
Bug ID: 72873
Summary: error: ‘asm’ operand has impossible constraints
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: hjl.tools at gmail dot com
CC: vmakarov at redhat dot com
Target Milestone: ---
On x86-64, I got
[hjl@gnu-6 asm-2]$ cat x.i
void foo (int disks, int start, int stop, unsigned long bytes, void **ptrs)
{
unsigned char **dptr = (unsigned char **)ptrs;
unsigned char *p, *q;
int d, z, z0;
z0 = stop;
p = dptr[disks-2];
q = dptr[disks-1];
for ( d = 0 ; d < bytes ; d += 512 ) {
asm volatile("#"
:
: "m" (p[d]), "m" (p[d+64]), "m" (p[d+128]), "m" (p[d+192]),
"m" (p[d+256]), "m" (p[d+320]), "m" (p[d+384]),
"m" (p[d+448]), "m" (q[d]), "m" (q[d+64]),
"m" (q[d+128]), "m" (q[d+192]), "m" (q[d+256]),
"m" (q[d+320]), "m" (q[d+384]), "m" (q[d+448]));
for ( z = z0-1 ; z >= start ; z-- ) {
asm volatile("#"
:
:
"m" (dptr[0][d]));
}
asm volatile("#"
:
: "m" (p[d]), "m" (p[d+64]), "m" (p[d+128]), "m" (p[d+192]),
"m" (p[d+256]), "m" (p[d+320]), "m" (p[d+384]),
"m" (p[d+448]), "m" (q[d]), "m" (q[d+64]),
"m" (q[d+128]), "m" (q[d+192]), "m" (q[d+256]),
"m" (q[d+320]), "m" (q[d+384]), "m" (q[d+448]));
}
}
[hjl@gnu-6 asm-2]$ make
/export/build/gnu/gcc/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O2
-fno-asynchronous-unwind-tables -S -o x.s x.i
x.i: In function ‘foo’:
x.i:10:5: error: ‘asm’ operand has impossible constraints
asm volatile("#"
^~~
x.i:23:5: error: ‘asm’ operand has impossible constraints
asm volatile("#"
^~~
Makefile:23: recipe for target 'x.s' failed
make: *** [x.s] Error 1
[hjl@gnu-6 asm-2]$
