Update 5/8/2020: The enclosed test case contains a "while (it00++ != g.end())" which will cause undefined behavior at runtime (which in the reported case is an attempted unaligned access). The problem arises on the last iteration where the compiler is forced to increment an iterator that is already pointing to g.end(), which is undefined behavior. Original Description: The following code results in an unaligned access failure in the ARM simulator when compiled with: armcl -mv5e -me --float_support=vfpv2 #include <map> #include <stdio.h> int main(void) {         std::map<int, char>::size_type n=9;         std::map<int, char> g;         char s[] = "contrived";         for (int i=0; i<n; i++) {             char k = s[i];             std::pair<const int, char> p((int)k, k);             g.insert(p);         }         int i00 = 0;         std::map<int, char>::iterator it00 = g.begin();         printf("start for loop\n");         while (it00++ != g.end())         {            printf("iteration %d\n", i00++);         }         printf("out of for loop\n");         return (1); }

The enclosed test case contains a "while (it00++ != g.end())" which will cause undefined behavior at runtime (which in the reported case is an attempted unaligned access). The problem arises on the last iteration where the compiler is forced to increment an iterator that is already pointing to g.end(), which is undefined behavior. User error.