Build race with API headers on Appveyor
Recently I've seen this a few times on Appveyor: https://ci.appveyor.com/project/DynamoRIO/dynamorio/builds/30344395
13686====> FAILURE in debug-internal-64 <====
13687debug-internal-64: **** 1 build errors ****
13688 C:\projects\dynamorio\build\build_debug-internal-64\include\dr_api.h(47) : fatal error C1083: Cannot open include file: 'dr_defines.h': No such file or directory
13689final package: **** 85 build errors ****
13690 ntdll_imports_x64.def : error LNK2001: unresolved external symbol __isascii
13691 ntdll_imports_x64.def : error LNK2001: unresolved external symbol __iscsym
13692 ntdll_imports_x64.def : error LNK2001: unresolved external symbol __iscsymf
13693 ntdll_imports_x64.def : error LNK2001: unresolved external symbol __toascii
13694 ntdll_imports_x64.def : error LNK2001: unresolved external symbol _atoi64
A re-build makes it go away. I think it's a race introduced recently -- and my theory is drdisas is missing a dependence. I will fix it.