simply set ccache env.vars instead of just warning about them

So that it works out of the box automagically.

Change-Id: I0a6c93824233eef6ce25c44762ec40770ec5110f
Reviewed-on: https://gerrit.libreoffice.org/71628
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

configure.ac

@@ -5075,18 +5075,6 @@ elif test "$enable_pch" = "no"; then
 else
     AC_MSG_ERROR([Unknown value for --enable-pch])
 fi
-if test -n "$ENABLE_PCH"; then
-    if test -n "$CCACHE"; then
-        if ! echo "$CCACHE_SLOPPINESS" | grep -q pch_defines | grep -q time_macros; then
-            AC_MSG_WARN([PCH with ccache requires CCACHE_SLOPPINESS to include 'pch_defines,time_macros'])
-            add_warning "PCH with ccache requires CCACHE_SLOPPINESS to include 'pch_defines,time_macros'"
-        fi
-        if test -z "$CCACHE_PCH_EXTSUM"; then
-            AC_MSG_WARN([It is recommended to set CCACHE_PCH_EXTSUM=1 for PCH with ccache.])
-            add_warning "It is recommended to set CCACHE_PCH_EXTSUM=1 for PCH with ccache."
-        fi
-    fi
-fi
 AC_SUBST(ENABLE_PCH)
 
 TAB=`printf '\t'`

solenv/gbuild/platform/com_GCC_defs.mk

@@ -35,6 +35,9 @@ else
 gb_AR := $(shell $(CC) -print-prog-name=ar)
 endif
 
+# shell setup (env.vars) for the compiler
+gb_COMPILER_SETUP :=
+
 ifneq ($(USE_LD),)
 gb_LinkTarget_LDFLAGS += -fuse-ld=$(USE_LD)
 endif
@@ -234,7 +237,7 @@ ifeq ($(COMPILER_PLUGINS_DEBUG),TRUE)
 gb_COMPILER_PLUGINS += -Xclang -plugin-arg-loplugin -Xclang --debug
 endif
 # set CCACHE_CPP2=1 to prevent clang generating spurious warnings
-gb_COMPILER_SETUP := CCACHE_CPP2=1
+gb_COMPILER_SETUP += CCACHE_CPP2=1
 gb_COMPILER_PLUGINS_SETUP := ICECC_EXTRAFILES=$(SRCDIR)/include/sal/log-areas.dox CCACHE_EXTRAFILES=$(SRCDIR)/include/sal/log-areas.dox
 gb_COMPILER_PLUGINS_WARNINGS_AS_ERRORS := \
     -Xclang -plugin-arg-loplugin -Xclang --warnings-as-errors
@@ -242,9 +245,7 @@ else
 # Set CCACHE_CPP2 to prevent GCC -Werror=implicit-fallthrough= when ccache strips comments from C
 # code (which still needs /*fallthrough*/-style comments to silence that warning):
 ifeq ($(ENABLE_WERROR),TRUE)
-gb_COMPILER_SETUP := CCACHE_CPP2=1
-else
-gb_COMPILER_SETUP :=
+gb_COMPILER_SETUP += CCACHE_CPP2=1
 endif
 gb_COMPILER_TEST_FLAGS :=
 gb_COMPILER_PLUGINS :=
@@ -286,4 +287,19 @@ endef
 
 gb_Helper_get_rcfile = $(1)rc
 
+ifneq ($(ENABLE_PCH),)
+# Enable use of .sum files for PCHs.
+gb_COMPILER_SETUP += CCACHE_PCH_EXTSUM=1
+# CCACHE_SLOPPINESS should contain pch_defines,time_macros for PCHs.
+gb_CCACHE_SLOPPINESS :=
+ifeq ($(shell test -z "$$CCACHE_SLOPPINESS" && echo 1),1)
+gb_CCACHE_SLOPPINESS := CCACHE_SLOPPINESS=pch_defines,time_macros
+else
+ifeq ($(shell echo "$$CCACHE_SLOPPINESS" | grep -q pch_defines | grep -q time_macros && echo 1),1)
+gb_CCACHE_SLOPPINESS := CCACHE_SLOPPINESS=$CCACHE_SLOPPINESS:pch_defines,time_macros
+endif
+endif
+gb_COMPILER_SETUP += $(gb_CCACHE_SLOPPINESS)
+endif
+
 # vim: set noet sw=4: