Questions tagged [comdat-folding]
6 questions
59
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Do distinct functions have distinct addresses?
Consider these two functions:
void foo() {}
void bar() {}
is it guaranteed that &foo != &bar?
Similarly,
template void foo() { }
is it guaranteed that &foo != &foo?
There are two linkers I know of that fold function…
Yakk - Adam Nevraumont
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Any way to generate warnings for function-pointer comparisons?
It took me forever to track down that there was a bug in my code being triggered by /OPT:ICF:
Because /OPT:ICF can cause the same address to be assigned to different functions or read-only data members (const variables compiled by using /Gy), it…
user541686
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Relation between MSVC Compiler & linker option for COMDAT folding
This question has some answers on SO but mine is slightly different. Before marking as duplicate, please give it a shot.
MSVC has always provided the /Gy compiler option to enable identical functions to be folded into COMDAT sections. At the same…
ForeverLearning
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Can a compiler elide the bodies of functions that are address-taken but never called?
Background information
Consider this simplified implementation of std::any (irrelevant parts omitted) and some code that uses it:
namespace std {
namespace details {
// Each instance of this function template has a different address
…
fghzxm
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Purpose of IMAGE_COMDAT_SELECT_NODUPLICATES
Microsoft C++ with the /Gy option will place every function in a different section so that the linker can omit unused functions, which may reduce the executable size.
In addition to placing every function in a different section, it also marks each…
rwallace
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COMDAT section name
I'm writing a linker for Windows binaries, and currently working on implementing COMDAT. I think I understand most of the specification, except that of the three records for a COMDAT section (the section header, section symbols and auxiliary…
rwallace
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