diff --git a/antennatracker/Makefile b/antennatracker/Makefile
index 7a0ad47192..182340e968 100644
--- a/antennatracker/Makefile
+++ b/antennatracker/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/ardupilot/Makefile b/ardupilot/Makefile
index 7a0ad47192..182340e968 100644
--- a/ardupilot/Makefile
+++ b/ardupilot/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/blimp/Makefile b/blimp/Makefile
index 7a0ad47192..182340e968 100644
--- a/blimp/Makefile
+++ b/blimp/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/copter/Makefile b/copter/Makefile
index 7a0ad47192..182340e968 100644
--- a/copter/Makefile
+++ b/copter/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/dev/Makefile b/dev/Makefile
index 7a0ad47192..182340e968 100644
--- a/dev/Makefile
+++ b/dev/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/mavproxy/Makefile b/mavproxy/Makefile
index 7a0ad47192..182340e968 100644
--- a/mavproxy/Makefile
+++ b/mavproxy/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/plane/Makefile b/plane/Makefile
index 7a0ad47192..182340e968 100644
--- a/plane/Makefile
+++ b/plane/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/planner/Makefile b/planner/Makefile
index 7a0ad47192..182340e968 100644
--- a/planner/Makefile
+++ b/planner/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/planner2/Makefile b/planner2/Makefile
index 7a0ad47192..182340e968 100644
--- a/planner2/Makefile
+++ b/planner2/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 
diff --git a/rover/Makefile b/rover/Makefile
index 7a0ad47192..182340e968 100644
--- a/rover/Makefile
+++ b/rover/Makefile
@@ -15,7 +15,7 @@ endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
-ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+ALLSPHINXOPTS   = -W -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source