winbuild: build with warning level 4

This is consistent with 7bc64561a2e63ca93e4b0b31d350773ba80955c2, which
changed the warning level from 3 to 4 for the Visual Studio project
files. But disable the level 4 warning C4127 "conditional expression is
constant", as that one is issued by older versions of the Windows SDK
as well as curl itself under some circumstances.

Closes https://github.com/curl/curl/pull/1667

diff --git a/winbuild/MakefileBuild.vc b/winbuild/MakefileBuild.vc
index 1d8210b3dab1b1e63cf79dff7b5484bac52d42a1..8f9aa1733258e1704f3e7b4934b1982524b4de63 100644 (file)
--- a/winbuild/MakefileBuild.vc
+++ b/winbuild/MakefileBuild.vc
@@ -56,11 +56,11 @@ CC = cl.exe
 !IF "$(VC)"=="6"\r
 CC_NODEBUG  = $(CC) /O2 /DNDEBUG\r
 CC_DEBUG    = $(CC) /Od /Gm /Zi /D_DEBUG /GZ\r
-CFLAGS     = /I. /I../lib /I../include /nologo /W3 /GX /DWIN32 /YX /FD /c /DBUILDING_LIBCURL\r
+CFLAGS      = /I. /I../lib /I../include /nologo /W4 /wd4127 /GX /DWIN32 /YX /FD /c /DBUILDING_LIBCURL\r
 !ELSE\r
 CC_NODEBUG  = $(CC) /O2 /DNDEBUG\r
-CC_DEBUG    = $(CC) /Od /D_DEBUG /RTC1 /Z7 /LDd /W3\r
-CFLAGS      = /I. /I ../lib /I../include /nologo /W3 /EHsc /DWIN32 /FD /c /DBUILDING_LIBCURL\r
+CC_DEBUG    = $(CC) /Od /D_DEBUG /RTC1 /Z7 /LDd\r
+CFLAGS      = /I. /I ../lib /I../include /nologo /W4 /wd4127 /EHsc /DWIN32 /FD /c /DBUILDING_LIBCURL\r
 !ENDIF\r
 \r
 LFLAGS     = /nologo /machine:$(MACHINE)\r
@@ -93,7 +93,7 @@ PDB_NAME_DLL_DEBUG     = $(BASE_NAME_DEBUG).pdb
 \r
 # CURL Command section\r
 PROGRAM_NAME = curl.exe\r
-CURL_CFLAGS   =  /I../lib /I../include /nologo /W3 /EHsc /DWIN32 /FD /c\r
+CURL_CFLAGS   =  /I../lib /I../include /nologo /W4 /wd4127 /EHsc /DWIN32 /FD /c\r
 CURL_LFLAGS   = /nologo /out:$(DIRDIST)\bin\$(PROGRAM_NAME) /subsystem:console /machine:$(MACHINE)\r
 CURL_RESFLAGS = /i../include\r
 \r