fixes copy constructor generation of classes containing 0-length arrays followed by exactly 1 trivial field (fixes #40682)

[lebedev.ri]

Test?

[jbigalet]

Fixes #40682

[jbigalet]

@lebedev.ri not a test, did I forgot to add anything? (sorry, it's my first time here)

[jbigalet]

regression test

[rjmccall]

Ah, thanks, seems like a reasonable fix.

[jbigalet]

Thanks!
I don't have commit rights btw

[rjmccall]

Committed as r358115.

clang/lib/CodeGen/CGClass.cpp

void addNextField(FieldDecl *F) {
 
       // The 'first' and 'last' fields are chosen by offset, rather than field
       // index. This allows the code to support bitfields, as well as regular
       // fields.
       uint64_t FOffset = RecLayout.getFieldOffset(F->getFieldIndex());
       if (FOffset < FirstFieldOffset) {
         FirstField = F;
         FirstFieldOffset = FOffset;
-      } else if (FOffset > LastFieldOffset) {
+      } else if (FOffset >= LastFieldOffset) {
         LastField = F;
         LastFieldOffset = FOffset;
       }
     }
 
     const VarDecl *SrcRec;
     const ASTRecordLayout &RecLayout;
     FieldDecl *FirstField;