Index: docs/SanitizerCoverage.rst
===================================================================
--- docs/SanitizerCoverage.rst
+++ docs/SanitizerCoverage.rst
@@ -144,6 +144,10 @@
 
 **Experimental, may change or disappear in future**
 
+**Note:** this instrumentation might be incompatible with dead code stripping
+(``-Wl,-gc-sections``), thus resulting in a significant binary size overhead.
+See `Bug 34636 <https://bugs.llvm.org/show_bug.cgi?id=34636>`_ for more info.
+
 With ``-fsanitize-coverage=pc-table`` the compiler will create a table of
 instrumented PCs. Requires either ``-fsanitize-coverage=inline-8bit-counters`` or
 ``-fsanitize-coverage=trace-pc-guard``.