[flang] [llvm] [CMake] Fix using precompiled headers with ccache (PR #131397)

[Kajetan Puchalski via llvm-commits]

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@@ -291,7 +291,7 @@ if(LLVM_CCACHE_BUILD)
       set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ${CCACHE_PROGRAM})
     else()
       if(LLVM_CCACHE_MAXSIZE OR LLVM_CCACHE_DIR OR
-         NOT LLVM_CCACHE_PARAMS MATCHES "CCACHE_CPP2=yes CCACHE_HASHDIR=yes")
+         NOT LLVM_CCACHE_PARAMS MATCHES "CCACHE_CPP2=yes CCACHE_HASHDIR=yes CCACHE_SLOPPINESS=pch_defines,time_macros")
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mrkajetanp wrote:

As written this will end up with compilation commands like
`"/usr/local/bin/cmake -E env CCACHE_CPP2=yes CCACHE_HASHDIR=yes CCACHE_SLOPPINESS=pch_defines,time_macros -- /usr/bin/ccache" /usr/bin/clang++ -DGTEST_H(..)`
and fail with
`/bin/sh: 1: /usr/local/bin/cmake -E env CCACHE_CPP2=yes CCACHE_HASHDIR=yes CCACHE_SLOPPINESS=pch_defines,time_macros -- /usr/bin/ccache: not found`
due to `launcher` getting put in quote marks. Removing the quotemarks from the last two lines in the patch above does not seem to make a difference, is there some way we could get around it?

https://github.com/llvm/llvm-project/pull/131397