[clang] [clang][docs] assert.h is not a good candidate for a textual header (PR #165057)

[Richard Smith via cfe-commits]

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@@ -421,13 +421,7 @@ As an example, the module map file for the C standard library might look a bit l
 
 .. parsed-literal::
 
-  module std [system] [extern_c] {
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zygoloid wrote:

Why remove the extern_c here? This seems like a pretty good example of a time when it'd make sense to use this attribute.

https://github.com/llvm/llvm-project/pull/165057