[clang] [Clang][Cygwin] Disable shared libs on Cygwin by default (PR #138119)

[Martin Storsjö via cfe-commits]

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@@ -106,7 +106,8 @@ if (LLVM_EXPORTED_SYMBOL_FILE)
                      DEPENDS ${LIBCLANG_VERSION_SCRIPT_FILE})
 endif()
 
-if(LLVM_ENABLE_PIC OR (WIN32 AND NOT LIBCLANG_BUILD_STATIC))
+if((NOT (WIN32 OR CYGWIN) AND LLVM_ENABLE_PIC) OR
+  ((WIN32 OR CYGWIN) AND NOT LIBCLANG_BUILD_STATIC))
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mstorsjo wrote:

Right, so in order not to change the behaviour for other windows platforms, this should probably be `if ((NOT CYGWIN AND LLVM_ENABLE_PIC) OR ((WIN32 OR CYGWIN) AND NOT LIBCLANG_BUILD_STATIC))`, i.e. removing the `WIN32 OR` part from the first part of the conditional?

https://github.com/llvm/llvm-project/pull/138119