[llvm-bugs] [Bug 46564] New: empty range-for loop over map is not optimized away

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=46564

            Bug ID: 46564
           Summary: empty range-for loop over map is not optimized away
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Loop Optimizer
          Assignee: unassignedbugs at nondot.org
          Reporter: trass3r at gmail.com
                CC: llvm-bugs at lists.llvm.org

#include <algorithm>
#include <map>
#include <string>
#include <vector>

using Map = std::map<int, std::vector<std::string>>;

void f1(const Map& m)
{
    for (const auto& p : m)
    { (void)p; }
}
void f2(const Map& m)
{
    std::for_each(m.begin(), m.end(), [](const std::pair<const int,
std::vector<std::string>>& p){
    (void)p; });
}

Does work for f2. gcc eliminates both:
https://godbolt.org/z/E-LCJV

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