diff --git a/library/Makefile b/library/Makefile
index 155e926..7ea8f74 100644
--- a/library/Makefile
+++ b/library/Makefile
@@ -278,14 +278,19 @@
 
 error.c: ../scripts/generate_errors.pl
 error.c: ../scripts/data_files/error.fmt
-error.c: $(wildcard ../include/mbedtls/*.h)
+error.c: $(filter-out %config%,$(wildcard ../include/mbedtls/*.h))
 error.c:
 	echo "  Gen   $@"
 	$(PERL) ../scripts/generate_errors.pl
 
 version_features.c: ../scripts/generate_features.pl
 version_features.c: ../scripts/data_files/version_features.fmt
-version_features.c: ../include/mbedtls/config.h
+## The generated file only depends on the options that are present in config.h,
+## not on which options are set. To avoid regenerating this file all the time
+## when switching between configurations, don't declare config.h as a
+## dependency. Remove this file from your working tree if you've just added or
+## removed an option in config.h.
+#version_features.c: ../include/mbedtls/config.h
 version_features.c:
 	echo "  Gen   $@"
 	$(PERL) ../scripts/generate_features.pl
diff --git a/programs/Makefile b/programs/Makefile
index 7b2ec51..7daa77c 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -147,7 +147,12 @@
 	$(PYTHON) ../scripts/generate_psa_constants.py
 
 test/query_config.c: ../scripts/generate_query_config.pl
-test/query_config.c: ../include/mbedtls/config.h
+## The generated file only depends on the options that are present in config.h,
+## not on which options are set. To avoid regenerating this file all the time
+## when switching between configurations, don't declare config.h as a
+## dependency. Remove this file from your working tree if you've just added or
+## removed an option in config.h.
+#test/query_config.c: ../include/mbedtls/config.h
 test/query_config.c: ../scripts/data_files/query_config.fmt
 test/query_config.c:
 	echo "  Gen   $@"
diff --git a/tests/Makefile b/tests/Makefile
index ef57169..c1620d6 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -64,7 +64,12 @@
 generated_files: $(GENERATED_FILES)
 
 $(GENERATED_DATA_FILES): scripts/generate_psa_tests.py
-$(GENERATED_DATA_FILES): ../include/psa/crypto_config.h
+## The generated file only depends on the options that are present in
+## crypto_config.h, not on which options are set. To avoid regenerating this
+## file all the time when switching between configurations, don't declare
+## crypto_config.h as a dependency. Remove this file from your working tree
+## if you've just added or removed an option in crypto_config.h.
+#$(GENERATED_DATA_FILES): ../include/psa/crypto_config.h
 $(GENERATED_DATA_FILES): ../include/psa/crypto_values.h
 $(GENERATED_DATA_FILES): ../include/psa/crypto_extra.h
 $(GENERATED_DATA_FILES): suites/test_suite_psa_crypto_metadata.data