diff options
Diffstat (limited to 'm4/ax_dll_string.m4')
| -rw-r--r-- | m4/ax_dll_string.m4 | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/m4/ax_dll_string.m4 b/m4/ax_dll_string.m4 new file mode 100644 index 0000000..241cd53 --- /dev/null +++ b/m4/ax_dll_string.m4 @@ -0,0 +1,87 @@ +# =========================================================================== +# http://autoconf-archive.cryp.to/ax_dll_string.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_DLL_STRING +# +# DESCRIPTION +# +# Tests for a bug currently in g++ 3.4.4 on Cygwin (maybe other targets +# with statically linked libstdc++?) where passing an empty std::string to +# a dll will cause a crash on destruction due to incorrect memory +# handling. See bug 24196 in gcc's bugzilla for more details: +# http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24196 +# +# LICENSE +# +# Copyright (c) 2008 Steven Brown <swbrown@variadic.org> +# +# Copying and distribution of this file, with or without modification, are +# permitted in any medium without royalty provided the copyright notice +# and this notice are preserved. + +dnl Plan: compile conftest-dll.cc, conftest-exe.cc. It has a 'crash' param +dnl that can be passed. Verify the compile worked and we can run it normally +dnl ok. Then, pass 'crash', test if it crashed, fail. + +AC_DEFUN([AX_DLL_STRING], +[ + AC_MSG_CHECKING(if the dll string test can be compiled) + cat << EOF > conftest-dll.cc +[ +#include <string> +using namespace std; + +void testit(std::string (*contentGet)()) { + contentGet(); +} +] +EOF + cat << EOF > conftest-exe.cc +[ +#include <string> +#include <cstring> +using namespace std; + +extern void testit(std::string (*contentGet)()); + +std::string contentGet() { + return string(""); // Anything other than empty string works. +} + +int main(int argc, char *argv[]) { + if(argc == 2 && strcmp(argv[1], "crash") == 0) { + testit(&contentGet); + } + return 0; +} +] +EOF + $CXX -shared $CFLAGS $CPPFLAGS conftest-dll.cc -o conftest-dll.dll >&AS_MESSAGE_LOG_FD && $CXX $CFLAGS $CPPFLAGS conftest-exe.cc conftest-dll.dll -o conftest-exe.exe >& AS_MESSAGE_LOG_FD + if test x"$?" = x"0"; then + AC_MSG_RESULT(yes) + + dnl Make sure it runs normally first. + AC_MSG_CHECKING(if the dll string test is usable) + if /bin/sh -c "(LD_LIBRARY_PATH=\"$PWD\" ./conftest-exe.exe)" >& AS_MESSAGE_LOG_FD 2>&1; then + AC_MSG_RESULT(yes) + + dnl Now we can check for the bug. + AC_MSG_CHECKING(if the dll string test is affected by gcc bug 24196) + if ! /bin/sh -c "(LD_LIBRARY_PATH=\"$PWD\" ./conftest-exe.exe crash)" >& AS_MESSAGE_LOG_FD 2>&1; then + AC_MSG_RESULT(yes) + + dnl We have the bug, user'll need to fix it. + AC_MSG_ERROR([*** This toolchain is affected by gcc bug 24196. For Cygwin as of 4/8/2006, you can downgrade to gcc/g++ 3.3.3 or check if there is a newer compiler available that's fixed.]) + else + AC_MSG_RESULT(no) + fi + else + AC_MSG_RESULT(no) + fi + else + AC_MSG_RESULT(no) + fi +]) |