3 files changed, 20 insertions, 4 deletions
diff --git a/cmake/scripts/windows/ArchSetup.cmake b/cmake/scripts/windows/ArchSetup.cmake
index 49a0f38a29..f0f8a085b5 100644
--- a/cmake/scripts/windows/ArchSetup.cmake
+++ b/cmake/scripts/windows/ArchSetup.cmake
@@ -62,9 +62,15 @@ set(SYSTEM_DEFINES -DWIN32_LEAN_AND_MEAN -DNOMINMAX -DHAS_DX -D__STDC_CONSTANT_M
 # Additional SYSTEM_DEFINES
 list(APPEND SYSTEM_DEFINES -DHAS_WIN32_NETWORK -DHAS_FILESYSTEM_SMB)
 
-# Make sure /FS is set for Visual Studio in order to prevent simultaneous access to pdb files.
+# The /MP option enables /FS by default.
 if(CMAKE_GENERATOR MATCHES "Visual Studio")
-  set(CMAKE_CXX_FLAGS "/permissive- /MP /FS ${CMAKE_CXX_FLAGS}")
+  if(DEFINED ENV{MAXTHREADS})
+    set(MP_FLAG "/MP$ENV{MAXTHREADS}")
+  else()
+    set(MP_FLAG "/MP")
+  endif()
+
+  set(CMAKE_CXX_FLAGS "/permissive- ${MP_FLAG} ${CMAKE_CXX_FLAGS}")
 endif()
 
 # Google Test needs to use shared version of runtime libraries
diff --git a/cmake/scripts/windows/CFlagOverrides.cmake b/cmake/scripts/windows/CFlagOverrides.cmake
index 1c796fda25..cd966899e1 100644
--- a/cmake/scripts/windows/CFlagOverrides.cmake
+++ b/cmake/scripts/windows/CFlagOverrides.cmake
@@ -1,5 +1,10 @@
 if(MSVC)
-  set(CMAKE_C_FLAGS "/D_UNICODE /DUNICODE /DRPC_USE_NATIVE_WCHAR /MP /DWIN32 /D_WINDOWS /W3 /Zi /arch:SSE2")
+  if(DEFINED ENV{MAXTHREADS})
+    set(MP_FLAG "/MP$ENV{MAXTHREADS}")
+  else()
+    set(MP_FLAG "/MP")
+  endif()
+  set(CMAKE_C_FLAGS "/D_UNICODE /DUNICODE /DRPC_USE_NATIVE_WCHAR ${MP_FLAG} /DWIN32 /D_WINDOWS /W3 /Zi /arch:SSE2")
   set(CMAKE_C_FLAGS_DEBUG "/D_DEBUG /MDd /Ob0 /Od /RTC1 /D_ITERATOR_DEBUG_LEVEL=0")
   set(CMAKE_C_FLAGS_RELEASE "/MD /Ox /Ob2 /Oi /Ot /Oy /GL /DNDEBUG")
 endif()
diff --git a/cmake/scripts/windows/CXXFlagOverrides.cmake b/cmake/scripts/windows/CXXFlagOverrides.cmake
index 44ae602bfe..72df9de168 100644
--- a/cmake/scripts/windows/CXXFlagOverrides.cmake
+++ b/cmake/scripts/windows/CXXFlagOverrides.cmake
@@ -1,5 +1,10 @@
 if(MSVC)
-  set(CMAKE_CXX_FLAGS "/D_UNICODE /DUNICODE /DRPC_USE_NATIVE_WCHAR /MP /DWIN32 /D_WINDOWS /W3 /GR /Zi /EHsc /arch:SSE2")
+  if(DEFINED ENV{MAXTHREADS})
+    set(MP_FLAG "/MP$ENV{MAXTHREADS}")
+  else()
+    set(MP_FLAG "/MP")
+  endif()
+  set(CMAKE_CXX_FLAGS "/D_UNICODE /DUNICODE /DRPC_USE_NATIVE_WCHAR ${MP_FLAG} /DWIN32 /D_WINDOWS /W3 /GR /Zi /EHsc /arch:SSE2")
   set(CMAKE_CXX_FLAGS_DEBUG "/D_DEBUG /MDd /Ob0 /Od /RTC1 /D_ITERATOR_DEBUG_LEVEL=0")
   set(CMAKE_CXX_FLAGS_RELEASE "/MD /Ox /Ob2 /Oi /Ot /Oy /GL /DNDEBUG")
 endif()