setlocale-null: avoid crashing the MSVC linker

[Bruno Haible]

The hack to define the DLL export stub directly in the source file is useful
with mingw and Cygwin. But it causes the MSVC 14 linker to crash. Seen when
building GNU gettext:

/bin/sh ../libtool  --tag=CC   --mode=link /home/bruno/msvc/compile cl -nologo  
-MD -Wl,--export-all-symbols -liconv  -ladvapi32 -no-undefined 
-export-symbols-regex 
'^([^g]|g[^l]|gl[^w]|glw[^t]|glwt[^h]|glwth[^r]|glwthr[^e]|glwthre[^a]|glwthrea[^d]).*'
 -version-info 9:6:1 -rpath /usr/local/msvc32/lib -L/usr/local/msvc32/lib 
-Wl,--disable-auto-import -o libintl.la  bindtextdom.lo dcgettext.lo 
dgettext.lo gettext.lo finddomain.lo hash-string.lo loadmsgcat.lo 
localealias.lo textdomain.lo l10nflist.lo explodename.lo dcigettext.lo 
dcngettext.lo dngettext.lo ngettext.lo plural.lo plural-exp.lo localcharset.lo 
threadlib.lo lock.lo relocatable.lo langprefs.lo localename.lo 
localename-table.lo log.lo printf.lo setlocale.lo setlocale-lock.lo 
setlocale_null.lo version.lo xsize.lo osdep.lo intl-compat.lo windows-mutex.lo 
windows-rwlock.lo windows-recmutex.lo windows-once.lo libintl.res.lo 
libtool: link: dumpbin -symbols  .libs/bindtextdom.obj .libs/dcgettext.obj 
.libs/dgettext.obj .libs/gettext.obj .libs/finddomain.obj .libs/hash-string.obj 
.libs/loadmsgcat.obj .libs/localealias.obj .libs/textdomain.obj 
.libs/l10nflist.obj .libs/explodename.obj .libs/dcigettext.obj 
.libs/dcngettext.obj .libs/dngettext.obj .libs/ngettext.obj .libs/plural.obj 
.libs/plural-exp.obj .libs/localcharset.obj .libs/threadlib.obj .libs/lock.obj 
.libs/relocatable.obj .libs/langprefs.obj .libs/localename.obj 
.libs/localename-table.obj .libs/log.obj .libs/printf.obj .libs/setlocale.obj 
.libs/setlocale-lock.obj .libs/setlocale_null.obj .libs/version.obj 
.libs/xsize.obj .libs/osdep.obj .libs/intl-compat.obj .libs/windows-mutex.obj 
.libs/windows-rwlock.obj .libs/windows-recmutex.obj .libs/windows-once.obj 
.libs/libintl.res.obj   | gawk '     {last_section=section; section=$ 3};     
/^COFF SYMBOL TABLE/{for(i in hide) delete hide[i]};     /Section length 
.*#relocs.*(pick any)/{hide[last_section]=1};     /^ *Symbol name *: /{split($ 
0,sn,":"); si=substr(sn[2],2)};     /^ *Type *: code/{print 
"T",si,substr(si,length(prfx))};     /^ *Type *: data/{print 
"I",si,substr(si,length(prfx))};     $ 0!~/External *\|/{next};     / 0+ UNDEF 
/{next}; / UNDEF \([^|]\)*()/{next};     {if(hide[section]) next};     {f="D"}; 
$ 0~/\(\).*\|/{f="T"};     {split($ 0,a,/\||\r/); split(a[2],s)};     
s[1]~/^[@?]/{print f,s[1],s[1]; next};     s[1]~prfx {split(s[1],t,"@"); print 
f,t[1],substr(t[1],length(prfx))}     ' prfx=^_ | sed '/ __gnu_lto/d' | 
/usr/bin/sed -e '/^[BCDGRS][ ]/s/.*[ ]\([^ ]*\)/\1,DATA/' | /usr/bin/sed -e 
'/^[AITW][ ]/s/.*[ ]//' | sort | uniq > .libs/intl.exp
libtool: link: /usr/bin/grep -E -e 
"^([^g]|g[^l]|gl[^w]|glw[^t]|glwt[^h]|glwth[^r]|glwthr[^e]|glwthre[^a]|glwthrea[^d]).*"
 ".libs/intl.exp" > ".libs/intl.expT"
libtool: link: mv -f ".libs/intl.expT" ".libs/intl.exp"
libtool: link: if test DEF = "`/usr/bin/sed -n -e 's/^[  ]*//' -e 
'/^\(;.*\)*$/d' -e 's/^\(EXPORTS\|LIBRARY\)\([         ].*\)*$/DEF/p' -e q 
.libs/intl.exp`" ; then cp ".libs/intl.exp" ".libs/intl-8.dll.def"; echo 
".libs/intl-8.dll.def" > ".libs/intl-8.dll.exp"; else /usr/bin/sed -e 
's/^/-link -EXPORT:/' < .libs/intl.exp > .libs/intl-8.dll.exp; fi
libtool: link:  /home/bruno/msvc/compile cl -nologo -o .libs/intl-8.dll  
.libs/bindtextdom.obj .libs/dcgettext.obj .libs/dgettext.obj .libs/gettext.obj 
.libs/finddomain.obj .libs/hash-string.obj .libs/loadmsgcat.obj 
.libs/localealias.obj .libs/textdomain.obj .libs/l10nflist.obj 
.libs/explodename.obj .libs/dcigettext.obj .libs/dcngettext.obj 
.libs/dngettext.obj .libs/ngettext.obj .libs/plural.obj .libs/plural-exp.obj 
.libs/localcharset.obj .libs/threadlib.obj .libs/lock.obj .libs/relocatable.obj 
.libs/langprefs.obj .libs/localename.obj .libs/localename-table.obj 
.libs/log.obj .libs/printf.obj .libs/setlocale.obj .libs/setlocale-lock.obj 
.libs/setlocale_null.obj .libs/version.obj .libs/xsize.obj .libs/osdep.obj 
.libs/intl-compat.obj .libs/windows-mutex.obj .libs/windows-rwlock.obj 
.libs/windows-recmutex.obj .libs/windows-once.obj .libs/libintl.res.obj   
--export-all-symbols --disable-auto-import    
/usr/local/msvc32/lib/iconv.dll.lib -L/usr/local/msvc32/lib -ladvapi32 
"@.libs/intl-8.dll.exp" -Wl,-DLL,-IMPLIB:".libs/intl.dll.lib"
cl : Command line warning D9002 : ignoring unknown option '--export-all-symbols'
cl : Command line warning D9002 : ignoring unknown option 
'--disable-auto-import'
   Creating library .libs/intl.dll.lib and object .libs/intl.dll.exp

LINK : fatal error LNK1000: Internal error during CImplib::ReSortExportNamePtrs

  Version 14.00.24210.0

  ExceptionCode            = C0000005
  ExceptionFlags           = 00000000
  ExceptionAddress         = 00FF07A2 (00FB0000) "C:\Program Files 
(x86)\Microsoft Visual Studio 14.0\VC\bin\link.exe"
  NumberParameters         = 00000002
  ExceptionInformation[ 0] = 00000000
  ExceptionInformation[ 1] = 0555999A

CONTEXT:
  Eax    = 03559C91  Esp    = 00EFD6A0
  Ebx    = 02000002  Ebp    = 00EFD6C0
  Ecx    = 0555999A  Esi    = 00000046
  Edx    = 03553BD8  Edi    = 00000047
  Eip    = 00FF07A2  EFlags = 00010206
  SegCs  = 00000023  SegDs  = 0000002B
  SegSs  = 0000002B  SegEs  = 0000002B
  SegFs  = 00000053  SegGs  = 0000002B
  Dr0    = 00000000  Dr3    = 00000000
  Dr1    = 00000000  Dr6    = 00000000
  Dr2    = 00000000  Dr7    = 00000000
make[5]: *** [Makefile:1500: libintl.la] Error 2


This patch avoids it.


2020-01-02  Bruno Haible  <address@hidden>

        setlocale-null: Avoid crashing the MSVC linker.
        * lib/setlocale-lock.c: Don't define IMP(gl_get_setlocale_null_lock) on
        MSVC.

diff --git a/lib/setlocale-lock.c b/lib/setlocale-lock.c
index 4bbe6eb..7dde32d 100644
--- a/lib/setlocale-lock.c
+++ b/lib/setlocale-lock.c
@@ -136,7 +136,7 @@ gl_get_setlocale_null_lock (void)
 
 # endif
 
-# if defined _WIN32 || defined __CYGWIN__
+# if (defined _WIN32 || defined __CYGWIN__) && !defined _MSC_VER
 /* Make sure the '__declspec(dllimport)' in setlocale_null.c does not cause
    a link failure when no DLLs are involved.  */
 #  if defined _WIN64 || defined _LP64