diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d220d55..86a1ea25 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -418,8 +418,8 @@ if(CMAKE_C_COMPILER_ID MATCHES "Clang" OR CMAKE_C_COMPILER_ID STREQUAL "GNU")
 	# These compiler flags can break the checks above so keep them here.
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pedantic -Wall -Wextra -Wshadow \
 -Wpointer-arith -Wcast-align -Wwrite-strings -Waggregate-return \
--Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Winline \
--Wredundant-decls -Wno-long-long -Wno-format-extra-args")
+-Wstrict-prototypes -Wmissing-prototypes \
+-Wno-long-long -Wno-format-extra-args")
 
 	if(BUILD_SHARED_LIBS AND UNIX AND NOT APPLE)
 		check_linker_flag(C "LINKER:--undefined-version" FLAG_UNDEFINED_VERSION)
diff --git a/configure.ac b/configure.ac
index 6cf7a32d..a47713e2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -518,7 +518,7 @@ else
     fi
 
     # warnings we'd like to see
-    AM_CFLAGS="${AM_CFLAGS} -pedantic -Wall -Wextra -Wshadow -Wpointer-arith -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Winline"
+    AM_CFLAGS="${AM_CFLAGS} -pedantic -Wall -Wextra -Wshadow -Wpointer-arith -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Wmissing-prototypes"
     # warnings we'd like to suppress
     AM_CFLAGS="${AM_CFLAGS} -Wno-long-long -Wno-format-extra-args"
     case "${host}" in