- add notes about what works and what doesn't

bochs-testing/plugin-test/test7-win32dll/README

@@ -53,3 +53,85 @@ EXPORTS
  module_init @ 1 ; 
  n_operations @ 2 DATA ; 
  operate__Fii @ 3 ; 
+
+---------------------------------------------
+Here is what works:
+g++ -mno-cygwin -c -o main.o ./main.cc
+dlltool --export-all --output-def uselib.def main.o
+dlltool --dllname uselib.exe --def uselib.def --output-lib uselib.a
+dlltool --dllname uselib.exe --output-exp uselib.exp --def uselib.def
+g++ -mno-cygwin -o uselib uselib.exp main.o 
+rm uselib.exp uselib.def
+g++ -mno-cygwin -shared -o module1.dll ./module1.cc uselib.a
+g++ -mno-cygwin -shared -o module2.dll ./module2.cc uselib.a
+
+What I wish would work:
+
+libtool gcc -mno-cygwin -c main.cc
+libtool gcc -mno-cygwin -export-dynamic -o main main.lo -rpath `pwd`/lib
+libtool gcc -mno-cygwin -c module1.cc 
+libtool gcc -mno-cygwin -no-undefined -module -o libmodule1.la module1.lo -rpath `pwd`/lib
+
+That fails with module1.cc: undefined reference to `_imp__version_string' and
+:module1.cc: undefined reference to `import stub for register_module(char const *)'
+
+Try to link with main.exe, since it exports the symbols that we need.
+
+libtool gcc -mno-cygwin -no-undefined -module -o libmodule1.la module1.lo -rpath `pwd`/lib main
+
+Same error
+
+libtool gcc -mno-cygwin -no-undefined -module -o libmodule1.la module1.lo -rpath `pwd`/lib main.exe
+
+Same error
+
+libtool gcc -mno-cygwin -no-undefined -module -o libmodule1.la module1.lo -rpath `pwd`/lib main.la
+
+libtool: link: cannot find the library `main.la'
+
+Try building import lib manually
+libtool g++ -mno-cygwin -c main.cc
+dlltool --export-all --output-def  main.def main.lo 
+dlltool --dllname main.exe --def main.def --output-lib libmainimport.a
+dlltool --dllname main.exe --def main.def --output-exp main.exp
+libtool g++ -mno-cygwin -o main.exe main.lo main.exp
+
+libtool gcc -mno-cygwin -no-undefined -module -o libmodule1.la module1.lo libimport-main.a -rpath `pwd`/lib
+
+
+
+
+
+
+The important part is that module1 and module2 are linked with "main", 
+the executable.  This would tell libtool that it should generate an
+import library corresponding to main, relink main 
+
+
+cygwin$ libtool gcc -mno-cygwin -c main.cc
+mkdir .libs
+gcc -mno-cygwin -c main.cc  -DDLL_EXPORT -DPIC -o .libs/main.lo
+In file included from main.cc:4:
+main.h:3: warning: #warning I will export DLL symbols for MAIN
+gcc -mno-cygwin -c main.cc -o main.o >/dev/null 2>&1
+mv -f .libs/main.lo main.lo
+cygwin$ libtool gcc -mno-cygwin -export-dynamic -o main main.lo -rpath `pwd`/lib
+gcc -mno-cygwin -o main.exe main.o -Wl,--export-dynamic   -Wl,--rpath -Wl,/home/bryce/bochs-testing/plugin-test/tmp/test7-win32dll/lib
+cygwin$ libtool gcc -mno-cygwin -c module1.cc 
+rm -f .libs/module1.lo
+gcc -mno-cygwin -c module1.cc  -DDLL_EXPORT -DPIC -o .libs/module1.lo
+In file included from module1.cc:2:
+main.h:6: warning: #warning I will import DLL symbols from MAIN
+gcc -mno-cygwin -c module1.cc -o module1.o >/dev/null 2>&1
+mv -f .libs/module1.lo module1.lo
+cygwin$ libtool gcc -mno-cygwin -no-undefined -module -o libmodule1.la module1.lo main -rpath `pwd`/lib
+rm -fr .libs/libmodule1.la .libs/libmodule1.* .libs/libmodule1.*
+generating symbol list for `libmodule1.la'
+ dlltool --export-all --exclude-symbols DllMain@12,_cygwin_dll_entry@12,_cygwin_noncygwin_dll_entry@12,DllMainCRTStartup@12,DllEntryPoint@12 --output-def .libs/cygmodule1-0.dll-def  module1.lo 
+ sed -e "1,/EXPORTS/d" -e "s/ @ [0-9]*//" -e "s/ *;.*$//" < .libs/cygmodule1-0.dll-def > .libs/libmodule1.exp
+if test "x`head -1 .libs/libmodule1.exp`" = xEXPORTS; then cp .libs/libmodule1.exp .libs/cygmodule1-0.dll-def; else echo EXPORTS > .libs/cygmodule1-0.dll-def; _lt_hint=1; cat .libs/libmodule1.exp | while read symbol; do set dummy $symbol; case $# in 2) echo " $2 @ $_lt_hint ; " >> .libs/cygmodule1-0.dll-def;; *) echo " $2 @ $_lt_hint $3 ; " >> .libs/cygmodule1-0.dll-def;; esac; _lt_hint=`expr 1 + $_lt_hint`; done; fi
+ gcc -Wl,--base-file,.libs/cygmodule1-0.dll-base -Wl,--dll -nostartfiles -Wl,-e,__cygwin_dll_entry@12 -o .libs/cygmodule1-0.dll  module1.lo  
+module1.lo(.text+0x37):module1.cc: undefined reference to `_imp__version_string'
+module1.lo(.text+0x55):module1.cc: undefined reference to `import stub for register_module(char const *)'
+collect2: ld returned 1 exit status
+