https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114297
Bug ID: 114297
Summary: Yet more problems with "definition in block does not
dominate use in block"
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: dcb314 at hotmail dot com
Target Milestone: ---
For this C++ code:
void __assert_fail(char *, int, const char *) __attribute__((__noreturn__));
template <class T> void max(T, T);
template <class T> struct SimpleVector {
T array;
int num;
T *getRef(int i) {
num - i ? void() : __assert_fail("", 7, __PRETTY_FUNCTION__);
return &array + i;
}
};
struct Extremes {
int minWidth;
int maxWidth;
};
int forceCalcColumnExtremes_cs;
struct Table {
SimpleVector<Extremes> colExtremes;
void forceCalcColumnExtremes();
};
void Table::forceCalcColumnExtremes() {
int minSumCols, maxSumCols;
for (int i; i; ++i) {
minSumCols += colExtremes.getRef(i)->minWidth;
maxSumCols += colExtremes.getRef(i)->maxWidth;
}
max(forceCalcColumnExtremes_cs, minSumCols);
max(forceCalcColumnExtremes_cs, maxSumCols);
}
compiled by recent gcc trunk, does this:
cvise $ ~/gcc/results/bin/g++ -c -w -O3 bug1022.cc
cvise $ ~/gcc/results/bin/g++ -c -w -O3 -march=znver3 bug1022.cc
bug1022.cc: In member function ‘void Table::forceCalcColumnExtremes()’:
bug1022.cc:20:6: error: definition in block 5 does not dominate use in block 3
20 | void Table::forceCalcColumnExtremes() {
| ^~~~~
for SSA_NAME: vect_maxSumCols_16.16_76 in statement:
vect_maxSumCols_16.16_90 = PHI <vect_maxSumCols_16.16_76(3)>
PHI argument
vect_maxSumCols_16.16_76
for PHI node
vect_maxSumCols_16.16_90 = PHI <vect_maxSumCols_16.16_76(3)>
during GIMPLE pass: vect
bug1022.cc:20:6: internal compiler error: verify_ssa failed
0x159e432 verify_ssa(bool, bool)
../../trunk.20210101/gcc/tree-ssa.cc:1203
0x1204a9d execute_function_todo
../../trunk.20210101/gcc/passes.cc:2095
The bug first seems to occur sometime between g:71244316cf714725
and g:10cbfcd60f9e5bdb, which is a distance of 43 commits.
