Support -fatal-warnings (without underscore) to be compatible with ld.gold

Originator:keithbsmiley
Number:rdar://46151736 Date Originated:17-Nov-2018 01:36 PM
Status:Open Resolved:
Product:Developer Tools Product Version:ld64-409.12
Classification:UI/Usability Reproducible:Always
 
Summary:
Currently if you have a cross-platform Swift PM project, you may want to pass `-Xlinker -fatal_warnings` for release builds (along with `-Xswiftc -warnings-as-errors`). To support this on both macOS and Linux, you have to do this conditionally in some script, so that you can pass -fatal_warnings to ld64, and -fatal-warnings to ld.gold. It would be great if ld64 supported a compatible flag to not have to add a platform conditional.

Steps to Reproduce:
1. On Linux and macOS in a SwiftPM project run `swift build -Xlinker -fatal-warnings`

Expected Results:
It works on both platforms

Actual Results:
It passes on Linux, and fails on macOS

Version:
ld64-409.12

Notes:
Attached is a possible patch (with tests!) to support this based on the Xcode 10.0.0 source dump from opensource.apple.com.

Comments

Here's the patch I attached: 


diff --git i/src/ld/Options.cpp w/src/ld/Options.cpp
index 09290a9..ab037f9 100644
--- i/src/ld/Options.cpp
+++ w/src/ld/Options.cpp
@@ -3103,7 +3103,7 @@ void Options::parse(int argc, const char* argv[])
 			else if ( strcmp(arg, "-w") == 0 ) {
 				// previously handled by buildSearchPaths()
 			}
-			else if ( strcmp(arg, "-fatal_warnings") == 0 ) {
+			else if ( strcmp(arg, "-fatal_warnings") == 0 ||  strcmp(arg, "-fatal-warnings") == 0 ) {
 				// previously handled by buildSearchPaths()
 			}
 			else if ( strcmp(arg, "-arch_errors_fatal") == 0 ) {
@@ -3997,7 +3997,7 @@ void Options::buildSearchPaths(int argc, const char* argv[])
 		else if ( strcmp(argv[i], "-w") == 0 ) {
 			sEmitWarnings = false;
 		}
-		else if ( strcmp(argv[i], "-fatal_warnings") == 0 ) {
+		else if ( strcmp(argv[i], "-fatal_warnings") == 0 ||  strcmp(argv[i], "-fatal-warnings") == 0 ) {
 			sFatalWarnings = true;
 		}
 		else if ( strcmp(argv[i], "-dependency_info") == 0 ) {
diff --git i/unit-tests/test-cases/fatal_warning/Makefile w/unit-tests/test-cases/fatal_warning/Makefile
index 6758bc0..9d5c621 100644
--- i/unit-tests/test-cases/fatal_warning/Makefile
+++ w/unit-tests/test-cases/fatal_warning/Makefile
@@ -34,6 +34,7 @@ run: all
 
 all:
 	${PASS_IFF_ERROR} ${CC} ${CCFLAGS} main.c -o main -pagezero_size 123 -Wl,-fatal_warnings  2>msgs.txt
+	${PASS_IFF_ERROR} ${CC} ${CCFLAGS} main.c -o main -pagezero_size 123 -Wl,-fatal-warnings  2>msgs.txt
 
 
 clean:
By keithbsmiley at Nov. 17, 2018, 9:38 p.m. (reply...)

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