https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81237
Bug ID: 81237
Summary: Cannot link when class methods compiled with different
levels of vectorization
Product: gcc
Version: 7.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ravi.kappiy...@cd-adapco.com
Target Milestone: ---
I have 4 files (2 CPP files, 1 header file, and 1 Makefile), shown below:
**test.h**
#ifndef test_h_
#define test_h_
#include
class A
{
public:
virtual ~A() {}
protected:
};
class B
{
public:
virtual std::string const func() const = 0;
protected:
B() {}
virtual ~B() {}
};
class C : public A
, public B
{
public:
~C();
private:
std::string const func() const;
};
#endif
**test.cpp**
#include "test.h"
C::~C() {}
**test2.cpp**
#include "test.h"
std::string const
C::func() const
{
return 0;
}
**Makefile**
all:
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu7.1.0/bin/g++ -O3
--param inline-unit-growth=1000 -fPIC -o test2.o -c test2.cpp
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu7.1.0/bin/g++ -fPIC -O3
--param inline-unit-growth=1000 -shared -z defs -Wl,--as-needed -shared
-Wl,-soname,libTest2.so -o libTest2.so test2.o
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu7.1.0/bin/g++ -O3
--param inline-unit-growth=1000 -fPIC -mavx512f -fabi-version=6 -o test.o -c
test.cpp
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu7.1.0/bin/g++ -fPIC -O3
--param inline-unit-growth=1000 -shared -z defs -Wl,--as-needed -shared
-Wl,-soname,libTest.so -o libTest.so test.o libTest2.so
old:
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu6.2.0/bin/g++ -O3
--param inline-unit-growth=1000 -fPIC -o test2.o -c test2.cpp
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu6.2.0/bin/g++ -fPIC -O3
--param inline-unit-growth=1000 -shared -z defs -Wl,--as-needed -shared
-Wl,-soname,libTest2.so -o libTest2.so test2.o
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu6.2.0/bin/g++ -O3
--param inline-unit-growth=1000 -fPIC -mavx512f -fabi-version=6 -o test.o -c
test.cpp
${MIRROR_HOME}/compilers/linux-x86_64-2.10.1/gnu6.2.0/bin/g++ -fPIC -O3
--param inline-unit-growth=1000 -shared -z defs -Wl,--as-needed -shared
-Wl,-soname,libTest.so -o libTest.so test.o libTest2.so
* **test2.cpp** is compiled with SSE2 instructions to create **libTest2.so**
* **test.cpp** is compiled with AVX-512 instructions (the flags "-mavx512f
-fabi-version=6" are added to it's compile)
* If both CPP files are instead compiled with the same vectorization level (via
the removal of the extra flags for **test.cpp** or the addition of the same
flags for **test2.cpp**), then the compile works as expected.
* The linker appears to be getting confused when some of the methods in the
class are compiled with one vectorization level, while other methods are
compiled with another, causing the "undefined reference" error.
* As far as I am aware, it is not illegal via the standard to compile certain
methods of a class with one level of vectorization and not other methods - this
appears to be a compiler bug.
* When using "make old" (i.e., using GNU 6.2 instead of GNU 7.1), the compile
works as expected even when using different levels of vectorization.
