https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97570
Bug ID: 97570 Summary: avr-gcc: error: 'void* memalign' redeclared as different kind of entity Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: matwey.kornilov at gmail dot com Target Milestone: --- Hi, While I am trying to build avr-gcc from master with Freestanding C++ standard library on x86_64 host system, I see the following compile error: ../../../../libstdc++-v3/libsupc++/new_opa.cc:56:18: error: 'void* memalign' redeclared as different kind of entity 56 | void *memalign(size_t alignment, size_t size); | ^~~~~~ ../../../../libstdc++-v3/libsupc++/new_opa.cc:39:18: note: previous declaration 'void* memalign(std::size_t, std::size_t)' 39 | extern "C" void *memalign(std::size_t boundary, std::size_t size); | ^~~~~~~~ ../../../../libstdc++-v3/libsupc++/new_opa.cc:56:18: error: 'size_t' was not declared in this scope; did you mean 'std::size_t'? 56 | void *memalign(size_t alignment, size_t size); | ^~~~~~ | std::size_t In file included from ../../../../libstdc++-v3/libsupc++/new_opa.cc:26: /usr/src/gcc/avr-obj/avr/libstdc++-v3/include/avr/bits/c++config.h:280:33: note: 'std::size_t' declared here 280 | typedef __SIZE_TYPE__ size_t; | ^~~~~~ ../../../../libstdc++-v3/libsupc++/new_opa.cc:56:36: error: 'size_t' was not declared in this scope; did you mean 'std::size_t'? 56 | void *memalign(size_t alignment, size_t size); | ^~~~~~ | std::size_t In file included from ../../../../libstdc++-v3/libsupc++/new_opa.cc:26: /usr/src/gcc/avr-obj/avr/libstdc++-v3/include/avr/bits/c++config.h:280:33: note: 'std::size_t' declared here 280 | typedef __SIZE_TYPE__ size_t; | ^~~~~~ I use binutils 2.35 and gcc 47d13acbda9a5d8eb57ff169ba74857cd54108e4 Steps to reproduce: 1. Build and install gcc without libstdc++: # ../configure --prefix=/usr --target=avr --enable-languages=c,c++ --disable-nls --disable-libssp --with-dwarf2 # make # make install 2. Build and install avr-libc 2.0 # ../configure --prefix=/usr --build=`../config.guess` --host=avr # make # make install 3. Rebuild gcc with Freestanding libstdc++ # ../configure --prefix=/usr --target=avr --enable-languages=c,c++ --disable-nls --disable-libssp --with-dwarf2 --with-newlib --disable-__cxa_atexit --disable-threads --disable-shared --enable-static --disable-sjlj-exceptions --enable-libstdcxx --enable-lto --disable-hosted-libstdcxx # make See the error. The following simple patch fixes the issue: --- a/libstdc++-v3/libsupc++/new_opa.cc +++ b/libstdc++-v3/libsupc++/new_opa.cc @@ -53,7 +53,7 @@ extern "C" # elif _GLIBCXX_HAVE_POSIX_MEMALIGN void *posix_memalign(void **, size_t alignment, size_t size); # elif _GLIBCXX_HAVE_MEMALIGN - void *memalign(size_t alignment, size_t size); + void *memalign(std::size_t alignment, std::size_t size); # endif } #endif Then gcc and libstdc++ are compiled and installed successfully without any further errors. But I doubt that this is correct way to handle this issue.