From 6dfa11e2f70ba4f7fa8252adaeb6597f8ad3ffb0 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Tue, 18 Jan 2022 17:25:11 +0200
Subject: [PATCH] make: improve diagnostic messages when the prebuilt tcc
 executable does not work/is missing

---
 GNUmakefile            | 13 +++++++++++--
 Makefile               |  1 +
 cmd/tools/detect_tcc.v | 15 +++++++++++++++
 make.bat               |  1 +
 4 files changed, 28 insertions(+), 2 deletions(-)
 create mode 100644 cmd/tools/detect_tcc.v

diff --git a/GNUmakefile b/GNUmakefile
index 3f7c7d3717..9d5d87c19c 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -76,7 +76,7 @@ endif
 endif
 endif
 
-.PHONY: all clean fresh_vc fresh_tcc
+.PHONY: all clean fresh_vc fresh_tcc check_for_working_tcc
 
 ifdef prod
 VFLAGS+=-prod
@@ -95,6 +95,7 @@ else
 	./v2.exe -o $(V) $(VFLAGS) cmd/v
 	rm -rf v1.exe v2.exe
 endif
+	@$(V) run cmd/tools/detect_tcc.v
 	@echo "V has been successfully built"
 	@$(V) -version
 
@@ -110,16 +111,21 @@ latest_vc:
 	@echo "Using local vc"
 endif
 
+check_for_working_tcc:
+	@$(TMPTCC)/tcc.exe --version > /dev/null 2> /dev/null || echo "The executable '$(TMPTCC)/tcc.exe' does not work."
+	
 fresh_vc:
 	rm -rf $(VC)
 	$(GITFASTCLONE) $(VCREPO) $(VC)
 
 ifndef local
 latest_tcc: $(TMPTCC)/.git/config
-	cd $(TMPTCC) && $(GITCLEANPULL)
+	@pushd . > /dev/null && cd $(TMPTCC) && $(GITCLEANPULL) && popd > /dev/null
+	@$(MAKE) --quiet check_for_working_tcc 2> /dev/null
 else
 latest_tcc:
 	@echo "Using local tcc"
+	@$(MAKE) --quiet check_for_working_tcc 2> /dev/null
 endif
 
 fresh_tcc:
@@ -128,12 +134,15 @@ ifndef local
 # Check wether a TCC branch exists for the user's system configuration.
 ifneq (,$(findstring thirdparty-$(TCCOS)-$(TCCARCH), $(shell git ls-remote --heads $(TCCREPO) | sed 's/^[a-z0-9]*\trefs.heads.//')))
 	$(GITFASTCLONE) --branch thirdparty-$(TCCOS)-$(TCCARCH) $(TCCREPO) $(TMPTCC)
+	@$(MAKE) --quiet check_for_working_tcc 2> /dev/null
 else
 	@echo 'Pre-built TCC not available for thirdparty-$(TCCOS)-$(TCCARCH) at $(TCCREPO), will use the system compiler: $(CC)'
 	$(GITFASTCLONE) --branch thirdparty-unknown-unknown $(TCCREPO) $(TMPTCC)
+	@$(MAKE) --quiet check_for_working_tcc 2> /dev/null
 endif
 else
 	@echo "Using local tccbin"
+	@$(MAKE) --quiet check_for_working_tcc 2> /dev/null
 endif
 
 $(TMPTCC)/.git/config:
diff --git a/Makefile b/Makefile
index 77a455ce5b..e37b6c4b51 100644
--- a/Makefile
+++ b/Makefile
@@ -9,3 +9,4 @@ all:
 	./v2 -o v $(VFLAGS) cmd/v
 	rm -rf v1 v2 vc/
 	@echo "V has been successfully built"
+	./v run ./cmd/tools/detect_tcc.v
diff --git a/cmd/tools/detect_tcc.v b/cmd/tools/detect_tcc.v
new file mode 100644
index 0000000000..1543dc7382
--- /dev/null
+++ b/cmd/tools/detect_tcc.v
@@ -0,0 +1,15 @@
+fn main() {
+	$if tinyc {
+		println('Your `tcc` is working. Good - it is much faster at compiling C source code.')
+		exit(0)
+	}
+
+	println('
+NB: `tcc` was not used, so unless you install it yourself, your backend
+C compiler will be `cc`, which is usually either `clang`, `gcc` or `msvc`.
+
+These C compilers, are several times slower at compiling C source code,
+compared to `tcc`. They do produce more optimised executables, but that
+is done at the cost of compilation speed.
+')
+}
diff --git a/make.bat b/make.bat
index ac64b35513..6b9a8e5726 100644
--- a/make.bat
+++ b/make.bat
@@ -240,6 +240,7 @@ echo ERROR: please follow the instructions in https://github.com/vlang/v/wiki/In
 exit /b 1
 
 :success
+.\v.exe run cmd\tools\detect_tcc.v
 echo  ^> V built successfully!
 echo  ^> To add V to your PATH, run `.\v.exe symlink`.