CMake: don't complain about missing nroff

The curl_nroff_check() was always being called, and complaining if
*NROFF wasn't found, even when not making the manual.

Only check for nroff (and complain) if actually making the manual

Closes #5817

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6a79b0b650f66d95abb707f0ab8fe3f60ad77f19..68842ee3eb16bf8d6c6adc4e8931f55e059ad580 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -225,7 +225,10 @@ if(ENABLE_IPV6 AND NOT WIN32)
   endif()
 endif()
 
-curl_nroff_check()
+if(USE_MANUAL)
+    #nroff is currently only used when USE_MANUAL is set, so we can prevent the warning of no *NROFF if USE_MANUAL is OFF (or not defined), by not even looking for NROFF..
+    curl_nroff_check()
+endif()
 find_package(Perl)
 
 cmake_dependent_option(ENABLE_MANUAL "to provide the built-in manual"