c++ - Is there a way to detect inline function ODR violations? -

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so have code in 2 separate translation units:

// a.cpp #include <stdio.h> inline int func() { return 5; } int proxy(); int main() { printf("%d", func() + proxy()); }  // b.cpp inline int func() { return 6; } int proxy() { return func(); }

when compiled result 10. when compiled -o3 (inlining on) 11.

i have done odr violation func().

it showed when started merging sources of different dll's fewer dll's.

i have tried:

  • gcc 5.1 -wodr (which requires -flto)
  • gold linker -detect-odr-violations
  • setting asan_options=detect_odr_violation=1 before running instrumented binary address sanitizer.

asan can supposedly catch other odr violations (global vars different types or that...)

this nasty c++ issue , amazed there isn't reliable tooling detecting it.

pherhaps have misused 1 of tools tried? or there different tool this?

edit:

the problem remains unnoticed when make 2 implementations of func() drastically different don't compiled same amount of instructions.

this affects class methods defined inside class body - implicitly inline.

// a.cpp struct { int data; a() : data(5){} };  // b.cpp struct { int data; a() : data(6){} };

legacy code lots of copy/paste + minor modifications after joy.

the simplest way detect such concerns copy functions single compilation unit (create 1 temporarily if needed). c++ compiler able detect , report duplicate definitions when compiling file.


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